Convert calculators
Free professional convert calculators with verified formulas and step-by-step solutions.
Oz to mL Converter
Convert between fluid ounces and milliliters. Handles both US (29.57 mL) and UK Imperial (28.41 mL) systems with a one-click toggle.
OpenOunces to Cups Converter
Convert fluid ounces to cups. Default is the US customary cup at exactly 8 fl oz, but recipes from Europe, the UK, and Japan use different c…
OpenmL to Oz Converter
Convert milliliters (mL) to fluid ounces (fl oz) with one click. Supports both US and UK Imperial systems. Includes quick picks for common v…
Openmg to mL Converter
Convert mg to mL with density or drug concentration. Includes presets for common substances (water, honey, oil) and children's medications (…
OpenKilometers to Miles Converter
Convert between kilometers and miles using the exact international factor (1 mile = 1.609344 km). Includes common race distances and a Fibon…
OpenGrams to Ounces Converter
Convert mass between grams and ounces. Avoirdupois (standard, 28.35 g) or troy (precious metals, 31.10 g) at one click. Cooking and gold quo…
OpenNm to ft-lb Converter
Convert torque values between Newton-meters (SI / European service manuals) and foot-pounds (US service manuals). Bidirectional, with common…
OpenKg to Lbs Converter
Convert mass between kilograms and pounds with the exact 0.45359237 factor (defined by the 1959 international yard and pound treaty). Body w…
OpenOunces to Grams Converter
Convert mass from ounces to grams using the exact 28.349523125 factor. Toggle between avoirdupois (everyday) and troy (gold/silver) at one c…
Openmm to Inches Conversion
Convert length between millimeters and inches with the exact 25.4 mm/inch factor. Bidirectional, with quick picks for common hardware sizes.
OpenOunces to Pounds Converter
Convert mass between ounces and pounds with the exact 16-to-1 ratio. Bidirectional, with quick picks for cooking and shipping weights.
OpenDays to Months Converter
Convert any number of days into months using the average calendar month of 30.4375 days. Bidirectional, with quick picks for 30, 60, 90, 180…
OpenTablespoons to Grams Converter
Tablespoon to gram converter that handles ingredient density. Flour, sugar, butter, honey, oil, salt and more - each with its own gram-per-t…
OpenMcg to Mg Converter
Convert mass between micrograms and milligrams. Exact factor (1 mg = 1000 mcg). Used for vitamin supplements, thyroid medication, and IU con…
OpenDays to Weeks Converter
Convert between days and weeks with the exact 1 week = 7 days factor. Quick picks for 7, 14, 21, 28, 30, 60, 90, and 365 days. Includes preg…
OpenGallons to Pounds Converter
Convert volume to mass for 14 common liquids: water 8.345 lb/gal, gasoline 6.20, diesel 7.10, milk 8.64. Uses the US gallon (3.785 L). UK Im…
OpenPounds to Ounces Converter
Convert pounds to ounces with the exact 1:16 ratio. Bidirectional, with quick picks for kitchen, postage, and infant weights.
OpenLbs to Kg Converter
Convert pounds to kilograms using the exact 1959 international pound (0.45359237 kg). Includes presets for body weight, gym plates, and US-t…
OpenLbs to Grams Converter
Convert mass between pounds and grams with the exact 453.59237 g factor defined by the 1959 International Yard and Pound Agreement. Bidirect…
OpenMonths to Years Converter
Convert any number of months into years, or years back into months, using the exact 12-month year. Bidirectional with quick picks for loan t…
OpenKnots to MPH Converter
Convert speed between knots and miles per hour using the 1.15078 mph/knot factor derived from the nautical mile (1852 m exact). Bidirectiona…
OpenHours to Days Converter
Convert time between hours and days using the exact 24-hour day. Bidirectional with quick picks for common spans (one day, 48h, 72h, one wee…
OpenInches to cm Converter
Convert length between inches and centimeters using the exact 2.54 cm/inch factor defined by the 1959 International Yard and Pound Agreement…
OpenPixels to Inches Converter
Convert pixels to inches at six DPI presets: 72, 96 (CSS reference), 150, 300, 600, and 1200. The W3C CSS spec fixes 96 DPI as the reference…
OpenmL to Cups Converter
Convert mL to cups using the cup standard that matches your recipe. NIST and FDA define the US legal cup at 240 mL; the recipe-traditional U…
OpenmL to Teaspoons Converter
Convert mL to teaspoons using the teaspoon standard that matches your context. The metric teaspoon is 5 mL exactly. The US customary teaspoo…
OpenQuarts to Cups Converter
Convert quarts and cups across US liquid, US dry, and imperial UK systems. 1 US liquid quart = 4 US cups = 946 mL. The dry quart is 16% larg…
OpenTeaspoons to mL Converter
Convert teaspoons to mL using the right teaspoon standard. The metric teaspoon is exactly 5 mL. The US customary teaspoon is 4.92892 mL. For…
OpenFahrenheit to Celsius Converter
Fahrenheit to Celsius converter using the exact formula °C = (°F − 32) × 5/9. Bidirectional, with quick picks for freezing (32 °F), body tem…
OpenMilliseconds to Seconds Converter
Milliseconds to seconds converter using the exact SI relationship: 1 s = 1000 ms. Bidirectional, with quick picks for the values web develop…
OpenCelsius to Fahrenheit Converter
Celsius to Fahrenheit converter using the exact formula °F = °C × 9/5 + 32. Bidirectional, with quick picks for a comfortable room (25 °C), …
OpenFeet to Inches Converter
Feet to inches converter using the exact relation 1 ft = 12 in. Bidirectional, with quick picks for human height (5 ft, 6 ft), lumber length…
OpenCM to Feet and Inches Converter
Convert centimeters to feet and inches (X ft Y in format) and back. Exact 1959 yard-and-pound ratio. Quick picks for common heights.
OpenPounds to Ounces Converter (lb to oz)
Convert pounds to ounces and back. Exact 16:1 ratio. Quick picks for cooking weights, recipe portions, and parcel rate brackets.
OpenCubic Feet Calculator
Calculate cubic feet from length, width, and height with per-dimension unit toggles for ft, in, m, and cm. Outputs cubic feet, cubic inches,…
OpenStone to Lbs Converter
Convert weight between stone and pounds using the exact factor of 14 lbs per stone, fixed by the UK Weights and Measures Act of 1835. Body w…
OpenTbsp to mL Converter
Convert tablespoons to milliliters using the right standard for your recipe. US tablespoon is 14.787 mL, metric is 15 mL exactly, Australian…
OpenGrams in mL Converter
Convert grams to mL using the density of the substance. Water is the only liquid where 1 g = 1 mL. Honey is 42% denser; oil is 9% less dense…
OpenHeight in Inches Converter
Convert height to total inches. Enter feet and inches, get total inches plus cm and meters. Inches-first format used by CDC, US military, an…
OpenKg to Liters Converter
Convert kilograms to liters and back for 12 common substances. 1 kg water = 1 L, 1 kg gasoline = 1.34 L, 1 kg honey = 0.70 L. Densities from…
OpenYards to Meters Converter
Convert yards to meters and back using the exact 1959 international yard definition (1 yd = 0.9144 m). Built-in quick picks for 1, 5, 10, 50…
OpenFeet to Meters Converter (ft to m)
Convert feet to meters and back using the exact 1959 international foot (1 ft = 0.3048 m). Quick picks for 1, 3, 5, 6, 10, 20, 50, and 100 f…
OpenPennies to Dollars Converter
Convert pennies to dollars using the 100-to-1 rule. Find penny jar values, weights, and how many pennies fit in a roll. Bidirectional with q…
OpenLiters to Gallons Converter
Convert L to gallons with the exact NIST conversion. Toggle between US (3.78541 L) and UK Imperial gallon (4.54609 L). Fuel-economy, beverag…
OpenLbs to Newton Converter
Convert force between pound-force (lbf) and newtons (N). Uses the exact factor 1 lbf = 4.4482216152605 N. Distinguishes pound-force (a force…
OpenInches to Fraction Calculator
Convert decimal inches to the closest binary fraction. Choose precision from 1/2 down to 1/64 of an inch, see the reduced fraction and the e…
OpenWeeks to Months Calculator
Convert between weeks and months using the Gregorian average of 4.348 weeks per month. Includes pregnancy week mapping (40 weeks = 9 months)…
OpenMeter to Mile Converter
Convert meters and miles with the exact 1959 international factor (1 mi = 1609.344 m). Preset distances for the 1500 m metric mile, the 5K, …
OpenPints to Cups Converter
Convert pints to cups across US customary and imperial UK systems. 1 US pint = 2 US cups = 473 mL. The imperial pint is 20% larger at 568 mL…
OpenCups to Oz Converter
Convert cups to fluid ounces with the exact 8 fl oz per US cup factor. Five cup standards covered: US customary, US legal (FDA), metric (250…
OpenFeet to Miles Converter
Convert feet to miles with the exact 1 mile = 5,280 feet factor - a statutory definition from 1593. Bidirectional. Quick picks for track dis…
OpenQuarts to Gallons Converter
Convert quarts to gallons with the exact 4:1 ratio. Holds in both US and UK systems - though the US gallon is 20% smaller than the imperial …
OpenKB to MB Converter
Convert KB to MB with a base toggle. Binary base (1024) matches Windows file sizes and RAM. Decimal base (1000) matches hard-drive labels an…
OpenFeet and Inches Calculator
Convert between feet and inches, decimal feet, total inches, and metric. Add or subtract two feet-and-inches measurements with automatic car…
OpenmL to Tbsp Converter
Convert mL to tablespoons using the right standard for your recipe. 15 mL = 1 metric tbsp, 14.787 mL = 1 US tbsp, 20 mL = 1 Australian tbsp.…
OpenNm to M Conversion
Convert nanometers (nm) to meters (m). 1 nanometer is one billionth of a meter. Bidirectional conversion with quick picks for visible light …
OpenDays to Years Converter
Convert days to years using 365.25 days per year (Julian average that accounts for leap years). Both directions, with quick presets for 1 mo…
OpenGallons to Quarts Converter
Convert volume between US gallons and US liquid quarts with the exact 4:1 ratio. Both directions, with quick presets for common kitchen and …
OpenQuarts to Pounds Converter
Convert volume to mass for 12 common substances. A US quart of water weighs 2.086 lb. A quart of honey weighs 3.01 lb. A quart of flour weig…
OpenNm to in-lbs Converter
Convert torque between Newton-meters and inch-pounds with the exact 8.85075 factor. Inch-pounds are the standard small-fastener unit for ele…
OpenCubic Feet to Gallons Converter
Convert volume between cubic feet and US gallons with the exact 1,728/231 factor. Both directions, with quick presets for pool, aquarium, an…
OpenPounds to Grams Converter
Convert mass between pounds and grams with the exact 453.59237 factor (defined by the 1959 international yard and pound treaty). Recipe scal…
OpenMeters to Feet Converter
Meters to feet converter using the exact relation 1 m = 3.28084 ft (= 1/0.3048). Bidirectional, with quick picks for human height (1.5 m, 1.…
OpenHours to Weeks Converter
Hours to weeks converter using the exact factor 1 week = 168 hours (7 days × 24 hours). Bidirectional, with quick picks for 24h, 40h work we…
OpenMg to Teaspoon Converter
Milligram to teaspoon converter that accounts for ingredient density. Mass and volume are different quantities, so the answer depends on wha…
OpenMinutes to Seconds Converter
Bidirectional minutes-to-seconds converter using the exact SI definition: 1 minute = 60 seconds. Useful for cooking, music BPM, sports timin…
OpenHours to Seconds Converter
Bidirectional hours-to-seconds converter using the exact SI definition: 1 hour = 3,600 seconds. For timeouts, video editing, shift planning …
OpenInch to Meter Converter
Bidirectional inch-to-meter converter using the exact 0.0254 m treaty factor. Useful for engineering, construction, screen sizes, sewing and…
OpenMB to GB Converter
Megabyte to gigabyte converter that handles both standards: binary (1,024 MB = 1 GB, used for RAM and Windows) and decimal (1,000 MB = 1 GB,…
OpenGrams to Fluid Ounces Converter
Convert grams (mass) to fluid ounces (volume) using ingredient density. Water 100 g = 3.38 fl oz, honey 100 g = 2.38 fl oz, olive oil 100 g …
OpenBar to PSI Converter
Convert pressure between bar and pounds per square inch (PSI) with the exact 14.5038 factor. Bidirectional. Quick picks for tyre pressure (2…
OpenCm to Mm Conversion
Convert centimeters to millimeters using the exact 1 cm = 10 mm SI relationship. No rounding - every cm-to-mm conversion is mathematically p…
OpenSquare Feet to Acres Converter
Square feet to acres converter using the exact 43,560 sqft per acre legal definition. Type sqft or acres; the other field updates instantly.…
OpenCC to mL Converter
One cubic centimeter (cc) equals exactly one milliliter (mL). The units are identical - same volume, two different names used in different f…
OpenAcreage Calculator
Acreage calculator that converts plot dimensions to acres, sqft, hectares, and square meters. Handles rectangular, circular, and triangular …
OpenMilitary Time Converter
Military time converter: 12-hour (HH:MM AM/PM) to 24-hour (HHMM) and back. Used by US military, aviation, hospitals, and railways. Bidirecti…
OpenMm to M Conversion
Convert millimeters to meters using the exact 1 mm = 0.001 m SI relationship. No rounding - every mm-to-m conversion is mathematically perfe…
OpenTeaspoons to Grams Converter
Teaspoons to grams converter with per-ingredient densities. 1 tsp granulated sugar = 4.2 g, 1 tsp table salt = 6.0 g, 1 tsp flour = 2.6 g. U…
OpenInch-Pounds to Foot-Pounds Calculator
Convert torque values between inch-pounds (in-lb) and foot-pounds (ft-lb) with the exact 12:1 ratio. Reference tables for SAE bolt specifica…
OpenMinutes to Hours Converter
Convert between minutes and decimal hours. Use 1 h = 60 min for payroll, billing, and timesheet conversion. Quick-pick presets for standard …
OpenCents to Dollars Converter
Convert cents to dollars using the 100-to-1 rule. 100 cents = $1.00. Bidirectional with quick picks, US coin denominations, and a reference …
OpenMetric to Inches Converter
Convert millimeters, centimeters, or meters to inches with one calculator. Switch the metric unit using the toggle; the exact NIST factor is…
OpenCentimeter Converter
Convert centimeters to seven other length units with one calculator. Inches, feet, millimeters, meters, kilometers, yards, miles — all…
OpenLiters to Pounds Converter
Convert liters to pounds using the actual density of 10 common liquids. 1 L of water = 2.20 lb, 1 L of honey = 3.13 lb, 1 L of gasoline = 1.…
OpenInch-lbs to Nm Converter
Convert torque between inch-pounds and Newton-meters with the exact 0.112985 factor. The default unit on US service manuals for small fasten…
OpenMcg to mL Converter
Convert micrograms to milliliters based on solution concentration (mcg/mL). Mass and volume are different dimensions, so the conversion is i…
OpenKg to Ounce Converter
Convert mass between kilograms and avoirdupois ounces with the exact 1959 international factor. 1 kg = 35.27396 oz. Includes troy-ounce comp…
OpenNickels to Dollars Converter
Convert between nickels and US dollars using the exact 5-cent value. 20 nickels = $1 and a standard Federal Reserve roll holds 40 nickels wo…
OpenAcres to Square Feet Converter
Convert area between acres and square feet using the exact 1 acre = 43,560 sq ft definition. Both directions, with quick presets for typical…
OpenFuel Economy Converter (MPG ↔ L/100km)
Convert vehicle fuel economy between US miles-per-gallon and liters-per-100-kilometers. The conversion is inverted - higher MPG is better, l…
OpenGrams to Calories Converter
Convert grams of any macronutrient to calories (kcal) and back, using the Atwater general factors: 4 kcal/g for carbs and protein, 9 kcal/g …
OpenKg to Stones Converter
Convert body weight between kilograms and UK stones using the exact factor 1 stone = 6.35029 kg (14 international pounds). The British and I…
OpenGram to Liter Conversion
Convert mass in grams to volume in liters using the density of each substance. Water: 1 L = 1000 g. Honey: 1 L = 1420 g. Oils: 1 L ≈ 915-920…
OpenYard to Mile Converter
Convert distance between yards and miles using the exact factor 1 mile = 1760 yards. Bidirectional, with quick picks for common sport distan…
OpenmL to μL Converter
Convert volume between milliliters and microliters using the exact factor 1 mL = 1000 μL. Bidirectional, with quick picks for pipette volume…
OpenHours to Minutes Converter
Convert time between hours and minutes using the exact factor 1 h = 60 min. Bidirectional, with quick picks for class periods, work shifts, …
OpenKg to Gallons Converter
Convert kilograms to US gallons using substance density. 1 kg water = 0.2642 gal, 1 kg gasoline = 0.3534 gal, 1 kg honey = 0.1860 gal. Built…
OpenPPM to mg/L Converter
Convert concentration between parts per million and milligrams per liter. For dilute aqueous solutions (water density 1.0 g/mL), 1 ppm = 1 m…
OpenSquare Inch to Square Foot Converter
Convert area between square inches and square feet using the exact factor 144. Bidirectional, with quick picks for common tile sizes (12x12,…
OpenCups to Quarts Converter
Convert between cups and quarts with the exact 1 quart = 4 cups (US liquid) factor. Bidirectional, with quick picks for common recipe and ba…
OpenGallons to Cups Converter
Convert between US gallons and US cups using the exact 1:16 ratio. 1 gal = 16 cups = 128 fl oz. Bidirectional with quick picks for quarter-g…
OpenmL to Lbs Converter
Convert milliliters to pounds using real substance densities. Water = 0.002205 lb per mL; honey = 0.003131; mercury = 0.0299. Pick the subst…
OpenNumber to Million Converter
Convert plain numbers to millions and back. 1,000,000 = 1 million. The bidirectional calculator handles the everyday news and finance shorth…
OpenOunce to Kg Converter
Convert mass between avoirdupois ounces and kilograms using the exact 0.028349523125 kg/oz factor, set by the 1959 International Yard and Po…
OpenCC to Oz Converter
Convert between cubic centimeters and US fluid ounces. 1 cc = 1 mL = 0.033814 fl oz; 1 fl oz = 29.5735 cc. Bidirectional with quick picks fo…
OpenBillion to Trillion Converter
Convert between billions and trillions using the US/UK short scale where 1 trillion equals exactly 1,000 billion. Useful for reading GDP, na…
OpenMillion to Billion Converter
Convert between millions and billions using the short scale where 1 billion equals 1,000 million. Built for journalists, analysts and anyone…
OpenCM to M Converter (Centimeters to Meters)
Convert between centimeters and meters using the exact SI relationship 1 m = 100 cm. Useful for body height, construction plans, scientific …
OpenCups to Pints Converter (US)
Convert between US cups and US pints using the exact factor 1 pint = 2 cups. Useful for scaling recipes, batch cooking, canning, and convert…
OpenLbs to Pounds Converter
Lbs is just an abbreviation for pounds. Both refer to the avoirdupois pound, defined as exactly 0.45359237 kilograms since 1959. This page e…
OpenmL to CC Converter (Milliliters to Cubic Centimeters)
Convert milliliters to cubic centimeters using the exact SI relationship 1 mL = 1 cc. The two units describe the same volume; mL is the pref…
OpenPint to Pound Converter
Convert pints to pounds using density. A US pint of water weighs about 1.04 lb (hence "a pint's a pound the world around"). Imperial UK pint…
OpenCubic Feet to Pounds Converter
Convert volume to mass for 11 common materials. Water is the baseline at 62.43 lb/ft³. Concrete weighs 150 lb/ft³, sand 100 lb/ft³, granite …
OpenGallons to Kilograms (gal to kg) Converter
Convert volume to mass for 10 common liquids. Water is the baseline at 3.785 kg per US gallon. Gasoline weighs 2.86 kg/gal, diesel 3.22 kg/g…
OpenGrams to Pounds (g to lbs) Converter
Convert grams to pounds (avoirdupois) with the exact 0.00220462 factor. 1 lb = 453.59237 g (1959 treaty value). Quick picks for cooking, die…
OpenKelvin to Celsius Converter
Convert temperature between Kelvin and Celsius using the exact SI offset of 273.15. C = K - 273.15. K = C + 273.15. Absolute zero is 0 K = -…
OpenDimes to Dollars Converter
Convert dimes to dollars and back with one click. Ten dimes make a dollar, fifty dimes fill a standard US Mint roll worth $5, and a thousand…
OpenMbps to Gbps Converter
Convert network speed between Mbps and Gbps using the SI decimal factor. 1 Gbps = 1000 Mbps for ethernet, broadband, and ISP speeds. Used by…
OpenkPa to PSI Conversion Calculator
Convert kilopascals to pounds per square inch and back with the exact NIST factor 6894.757 Pa per psi. Bidirectional with quick picks for ti…
OpenGrams to mL Converter
Convert grams to milliliters with ingredient-specific densities. Water is 1:1 by definition, but flour is 0.53 g/mL and honey is 1.42 g/mL. …
Openmg to cc Converter
Convert milligrams to cubic centimeters using the concentration of the substance. Bidirectional, with built-in presets for common medication…
OpenHours to Years Converter
Convert between hours and years bidirectionally. Standard 365-day year = 8,760 hours. Julian 365.25-day year = 8,766 hours. Leap year = 8,78…
OpenMM to Foot Converter
Convert millimeters to feet and feet to millimeters bidirectionally. Uses the exact 1 ft = 304.8 mm definition from the 1959 International Y…
OpenMPa to PSI Conversion Calculator
Convert megapascals to pounds per square inch and back using the exact NIST factor. 1 MPa equals 145.038 psi. Bidirectional with quick picks…
OpenGallons to Pints Converter
Convert volume between gallons and pints using the exact 8:1 ratio. Works for US liquid, US dry, and imperial (UK) systems - the gallons-to-…
OpenKg to mL Converter
Convert kilograms to milliliters for 10 common substances. 1 kg water = 1000 mL, 1 kg honey = 704 mL, 1 kg gasoline = 1337 mL. Densities fro…
OpenKilometers to Meters Conversion
Convert kilometers to meters. The conversion is exact: 1 km = 1000 m by the SI metric prefix “kilo”. Includes preset race distan…
Openml to kg Converter
Convert milliliters to kilograms and back for 10 common substances. 1000 mL water = 1 kg, 1000 mL gasoline = 0.748 kg, 1000 mL honey = 1.42 …
OpenGallons to Cubic Feet Converter
Convert US liquid gallons to cubic feet using the exact factor 1 ft³ = 7.480519 gallons. Used for water tanks, swimming pools, aquariums, an…
OpenLbs to Stone Converter
Convert pounds to UK stones using the exact factor 1 stone = 14 international pounds. The British and Irish body-weight unit, with quick pic…
OpenCm to Inches Converter
Convert centimeters to inches using the exact factor 1 inch = 2.54 cm. Fixed legally by the 1959 International Yard and Pound Agreement. For…
OpenLbs to PSI Calculator
Convert pounds-force to PSI. Pressure equals force divided by area, so 100 lbs spread over 2 in² is 50 PSI. The same 100 lbs on a stiletto h…
OpenMinutes to Days Converter
Convert minutes to days using the exact factor 1 day = 1440 minutes (24 × 60). Handle uptime logs, project timelines, and billing peri…
OpenmmHg to atm Conversion
Convert pressure between millimeters of mercury and atmospheres. 1 atm equals exactly 760 mmHg by the 1954 international definition. Used in…
OpenPounds to Lbs Converter
Pounds and lbs are identical - two ways to write the same unit of mass. Both refer to the avoirdupois pound, exactly 0.45359237 kg since 195…
OpenPPM Calculator
Convert concentration between PPM, PPB, PPT, percent, mg/L, and mg/kg. Six common units of trace concentration with exact conversion factors…
OpenMetric to Standard Converter
Convert between metric and US standard (customary) units using exact NIST-published factors. Covers length (m to ft, km to mi, cm to in), ma…
OpenMile Conversion Calculator
Convert miles to any common distance unit using exact factors. 1 mile = 1.609344 km, 5280 ft, 1760 yards. Also handles inches and nautical m…
OpenPints to Gallons Converter
Convert volume between pints and gallons using the exact 8:1 ratio. Works for US liquid, US dry, and UK imperial systems - the pints-to-gall…
OpenSeconds to Hours Converter
Convert time between seconds and hours using the exact 3600 factor (60 minutes per hour x 60 seconds per minute). Bidirectional, with anchor…
OpenCM Height Conversion Calculator
Convert height between centimeters and feet+inches using the exact 2.54 cm per inch factor. Two-way conversion with meters and decimal-foot …
OpenDrops to mL Converter
Convert drops to milliliters using USP-standard medical droppers (20 gtt/mL), essential oil droppers (15 gtt/mL), or IV macrodrip/microdrip …
OpenMilliseconds Converter
Convert milliseconds to seconds, minutes, or hours using the exact SI definition (1 s = 1,000 ms). A target-unit toggle handles all three co…
OpenSeconds to Minutes Converter
Convert seconds to minutes using the exact SI definition (1 min = 60 s). Useful for cooking timers, music timing, sports splits, video editi…
OpenWeeks to Years Converter
Convert weeks to years using the exact Gregorian-calendar average of 52.1786 weeks per year (365.2425 days / 7). Useful for pregnancy timeli…
OpenFoot to Centimeter Converter
Convert length between feet and centimeters using the exact 30.48 cm/ft factor fixed by the 1959 International Yard and Pound Agreement. Inc…
OpenSquare Meters to Square Feet Converter
Convert area between square meters and square feet using the exact 1 ft = 0.3048 m definition. 1 m² equals 10.7639 sq ft; the factor is math…
OpenBar to PSIG Converter
Convert bar gauge pressure to PSIG (pounds per square inch, gauge). 1 bar = 14.5038 PSI, but gauge means relative to atmosphere, so 1 bar ga…
OpenHeight Converter
Convert body height between centimeters and feet+inches with the exact 1959 standard (1 in = 2.54 cm). Dual-input layout, shows meters, tota…
OpenInch Converter
Convert inches to any metric or imperial length unit. Exact 1 in = 25.4 mm by the 1959 International Yard and Pound Agreement. Pick mm, cm, …
OpenKm to Feet Conversion
Convert distance between kilometres and feet using the exact 0.3048 m per foot definition. Includes aviation flight levels, running distance…
OpenMbps Converter
Convert internet speed from Mbps to MB/s, Kbps, Gbps, KB/s, or GB/s. 1 Mbps = 0.125 MB/s (divide by 8). Pick the target unit; the converter …
OpenCubic Inches to Gallons Converter
Convert between cubic inches and gallons using the exact factors: 1 US gallon = 231 in³ (defined by law in 1707) and 1 imperial gallon = 277…
OpenFluid Ounces to Pounds Converter
Convert US fluid ounces (volume) to pounds (mass) for 10 common substances. The conversion depends on density: 1 fl oz of water weighs 0.065…
OpenKelvin to Fahrenheit Converter
Convert between kelvin (K) and fahrenheit (°F) using the exact relation: F = (K − 273.15) × 9/5 + 32, or equivalently K × 1.8 − 459.67. Abso…
OpenLiters to cL Converter
Convert between liters (L) and centiliters (cL) using the exact metric factor: 1 L = 100 cL. The centiliter is the standard bottle-label uni…
OpenOz to CC Converter
Convert US fluid ounces to cubic centimeters with the exact 29.5735 factor. 1 fl oz = 29.5735 cc = 29.5735 mL. Reverse: 1 cc = 0.0338 fl oz.…
OpenHectares to Acres Converter
Convert land area between hectares and acres. One hectare equals 2.47105 acres, one acre equals 0.4047 hectares. Used for property, farming,…
OpenKg/cm² to PSI Converter
Convert pressure between kilogram-force per square centimeter (kgf/cm², the technical atmosphere) and pounds per square inch (psi) using the…
OpenMg to Lbs Converter
Convert between milligrams (mg) and pounds (lbs) using the exact 1959 international pound: 1 lb = 453.59237 g = 453,592.37 mg. Useful for ph…
OpenMg to Tablespoon Converter
Milligram to tablespoon converter that accounts for ingredient density. A tablespoon of honey weighs 21,300 mg; a tablespoon of cocoa powder…
OpenPSIG to PSIA Converter
Convert between gauge (PSIG) and absolute (PSIA) pressure with adjustable atmospheric pressure for altitude. Default 14.696 psi at sea level…
OpenCups to Gallons Converter
Convert between US cups and US liquid gallons with the exact 1 gal = 16 cups factor. Bidirectional, with quick picks for common beverage and…
OpenMil to MM Conversion
Convert mil (one-thousandth of an inch) to millimeters and back. Exact 0.0254 mm factor - the same value used by PCB designers, coating insp…
OpenSeconds to Years Conversion
Convert seconds to years and back using the Julian-year definition (31,557,600 s) used in astronomy and physics. Includes leap-year and Greg…
OpenGallon Conversion Calculator
Convert US gallons to seven other volume units with one toggle. Liters, UK gallons, quarts, pints, cups, fluid ounces, and milliliters - exa…
OpenMetric to Imperial Conversion Calculator
Convert metric to imperial units across length, mass, volume, and temperature. Toggle the unit type and enter a value in either system; the …
OpenMillion to Thousand Converter
Convert millions to thousands instantly. 1 million = 1,000 thousand. Includes lakh, crore, billion and the short-scale vs. long-scale distin…
OpenNewton to Joules Calculator
Convert newtons to joules with the work equation W = F x d. Enter any two of force, distance, and energy; the calculator solves for the thir…
OpenTorque to Horsepower Calculator
Torque to horsepower calculator that solves the SAE J1349 power identity in either direction. Inputs: torque in lb-ft or N·m, plus engine sp…
OpenTorr to Atm Converter
Convert torr to atmospheres with the exact BIPM 1954 factor (1 atm = 760 torr). Plus mmHg, Pascal, psi and bar reference values for laborato…
OpenLot Size to Acres Calculator
Convert lot dimensions to acres. Enter length and width in feet, meters, or yards; output includes acres, square feet, square meters, hectar…
Openmm to inches, cm, m, ft Converter
Convert millimeters to centimeters, meters, inches, feet, yards, kilometers, or micrometers. Uses the exact 1959 definition: 1 inch = 25.4 m…
OpenStone to Kg Converter
Convert body weight between stone and kilograms with the exact 6.35029318 kg factor (14 lbs avoirdupois). Built for UK and Irish weight trac…
OpenInches to Yards Converter
Convert length between inches and yards using the exact 1 yd = 36 in factor, defined by the 1959 International Yard and Pound Agreement. Inc…
OpenLowercase to Uppercase Converter
Toggle any text between five case styles — UPPERCASE, lowercase, Title Case, Sentence case, and tOGGLE cASE. Unicode-aware so accents,…
OpenMil to Inch Converter
Convert length between mils (thousandths of an inch) and inches with the exact 1 mil = 0.001 in factor. Standard reference for paint coating…
OpenMinutes to Years Converter
Convert between minutes and years using the Julian average of 525,960 minutes per year (365.25 days × 1440 minutes). Quick picks cover…
OpenkPa to atm Conversion Calculator
Convert pressure between kilopascals and standard atmospheres using the exact 101.325 kPa = 1 atm definition. Sea-level pressure is 101.325 …
OpenSeconds to Days Converter
Convert time between seconds and days using the exact 1 day = 86,400 seconds factor. Outputs full D HH:MM:SS breakdown and conversions to ho…
OpenGallons to Grams Converter
Convert volume in US gallons to mass in grams for 8 common liquids. Water = 3785.41 g/gal exact. Milk, honey, oil, fuel, and ethanol covered…
OpenMetric to SAE Wrench Conversion Calculator
Find the closest SAE wrench size for any metric millimeter value (and back). Uses 25.4 mm per inch exactly. Flags whether the metric and SAE…
Openpsi to atm Conversion Calculator
Convert pressure between pounds per square inch and standard atmospheres using the exact 14.69594877 psi = 1 atm definition. Covers tire, sc…
Openpsi to Inches of Water Conversion Calculator
Convert pressure between psi and inches of water column. 1 psi = 27.7076 inH2O at 4 degrees C. Essential for HVAC ductwork, natural gas appl…
OpenMillion to Lakh Converter
Convert between the Western million (1,000,000) and the Indian lakh (100,000). 1 million = 10 lakhs, exactly. Useful for NRI banking, Indian…
OpenNewton-Meter Torque Converter
Convert torque between newton-meters (SI) and foot-pounds, inch-pounds, or kilogram-force meters. Toggle the target unit, type either value,…
OpenPa to PSI Converter
Convert pressure between pascals (SI) and pounds per square inch (US/UK). The factor is exact: 1 psi = 6894.757293168 Pa. Tire, hydraulic, v…
OpenRGB to HEX Converter
Convert between RGB (0-255 per channel) and HEX (#RRGGBB) color notation. Live color swatch, HSL and CMYK readouts, and ready-to-paste CSS. …
OpenAngstrom to Nm Conversion
Convert between angstroms (Å, 10⁻¹⁰ m) and nanometers (nm, 10⁻⁹ m). The relation is exact: 1 Å = 0.1 nm. Used in crystallography, spectrosco…
OpenCC to Grams Converter
Convert cc (cubic centimeters, equal to mL) to grams using each substance density. Water, milk, oil, honey, fuel, ethanol, even mercury at 1…
OpenCrore to Million Converter
Convert between the Indian crore (10,000,000) and the Western million (1,000,000). 1 crore equals 10 million, exactly. Built for NRI banking…
OpenGr to Tsp Converter
Convert grams to teaspoons by ingredient. Each food has its own density, so 5 g of sugar, salt, flour, and oregano fill different fractions …
OpenKnots to km/h Converter
Convert speed between knots (nautical miles per hour) and kilometres per hour. The factor 1.852 is exact by international definition (1929 H…
OpenCC to Liter Converter
Convert cubic centimeters to liters with the exact 1000:1 factor. 1 cc equals 1 mL by SI definition. Engine sizes, medical doses, and lab vo…
OpenCubic Feet to Cubic Meters Converter
Bidirectional volume conversion between cubic feet and cubic meters. Uses the exact factor derived from 1 ft = 0.3048 m, giving 1 ft³ = 0.02…
OpenFeet to Yards Conversion
Bidirectional conversion between feet and yards using the exact 1 yard = 3 feet relationship from the 1959 International Yard and Pound Agre…
OpenKSI to PSI Conversion Calculator
Bidirectional conversion between ksi (kips per square inch) and psi (pounds per square inch) for structural engineering, material testing, a…
OpenMeters to Feet Converter (m to ft)
Bidirectional conversion between meters and feet using the exact 1 foot = 0.3048 meters factor from the 1959 International Yard and Pound Ag…
OpenAcres to Hectares Converter
Convert land area between acres and hectares. The conversion is exact: 1 acre = 4046.8564224 square meters and 1 hectare = 10000 square mete…
OpenGallon to Tons Converter
Convert volume in US gallons to mass in short tons (2000 lb). 1000 US gal water = 4.16 short tons. Density picker for 13 liquids; NIST and U…
OpenHardness Conversion Calculator
Convert hardness readings between five common scales: Rockwell B and C, Brinell, Vickers and Shore D. Built on ASTM E140 anchor data for ste…
OpenkPa to mmHg Conversion Calculator
Convert pressure between kilopascals (kPa) and millimeters of mercury (mmHg) using the SI-derived factor 1 kPa = 7.50062 mmHg. Useful for me…
OpenWeight Converter
Convert kilograms to any of 8 weight units: pound (lb), ounce (oz), gram (g), stone (st), milligram, metric tonne, short ton, long ton. Exac…
OpenBar to ATM Converter
Bar to atmosphere converter using the BIPM-defined relationship: 1 atm = 1.01325 bar exactly. Bidirectional, with quick picks for tires, scu…
OpenCubic Meter Converter
Convert volume from cubic meters into liters, US or imperial gallons, cubic feet, cubic yards, cubic inches, or cubic centimeters. The unit …
OpenJoules to Volts Converter
Convert energy in joules to potential difference in volts. The formula is V = J / Q where Q is electric charge in coulombs. The calculator s…
OpenLiters to Cubic Centimeters
Convert volume between liters (L) and cubic centimeters (cm³, cc) with the exact 1 L = 1000 cc relationship. Used for engine displacement, l…
Openm/s to km/h Converter
Meters per second to kilometers per hour converter. The factor is exactly 3.6 (3600 s / 1000 m). Bidirectional with quick picks for cycling,…
OpenPounds to Stone Converter
Pounds to stone converter using the standardised UK definition: 1 stone = exactly 14 pounds = 6.35029 kg. Bidirectional, with quick picks fo…
OpenSquare Miles to Square Kilometers
Convert land area between square miles (mi²) and square kilometers (km²) using the exact factor 1 mi² = 2.58998811 km². Built for GIS, real …
OpenATM to Pascals Converter
ATM to Pascals converter using the exact BIPM-defined factor 1 atm = 101325 Pa. Bidirectional, with quick picks for tire pressure, weather s…
OpenImperial to Metric Conversion Calculator
Convert imperial to metric units across length, mass, volume, and temperature. Toggle the unit type and enter a value in either system; the …
OpenTemperature Converter
Universal temperature converter for all four scales (Celsius, Fahrenheit, Kelvin, Rankine). Toggle from and to units, with absolute-zero val…
OpenByte Converter
Byte converter that handles every common storage unit: KB, MB, GB, TB. Toggle between binary (1,024-based, used by RAM and Windows) and deci…
OpenYard Conversion Calculator
Yard conversion calculator that switches between yards and four target units: feet (1 yd = 3 ft), meters (1 yd = 0.9144 m), inches (1 yd = 3…
OpenLight Year Conversion Calculator
Light year conversion calculator for astronomy: convert light-years to kilometers (9.461 × 10<sup>12</sup>), miles (5.879 × 10<s…
OpenLength Converter
Universal length converter covering nine units: millimeters, centimeters, meters, kilometers, inches, feet, yards, statute miles and nautica…
OpenDecimeter to Meter Converter
Convert between decimeters and meters using the exact SI factor: 1 m = 10 dm. Bidirectional, instant, and works in both directions with adju…
OpenKelvin Converter
A Kelvin converter for the SI base unit of thermodynamic temperature. Enter a value in K and get Celsius, Fahrenheit, and Rankine at once. U…
OpenKilometer Converter
A kilometer converter for distance work. Enter any value in km and see meters, miles, yards, feet, and nautical miles at once. Useful for tr…
OpenCelsius Converter
A Celsius converter for everyday and laboratory work. Enter a value in °C and see Fahrenheit, Kelvin, and Rankine at once. Useful for we…
OpenNumber to Billion Converter
Convert any plain number to billion, million, or trillion. 1 billion equals 1,000,000,000 in the short scale used by US, UK, and modern fina…
OpenFahrenheit Converter
Fahrenheit converter with a target toggle for Celsius, Kelvin, or Rankine. Uses the exact NIST conversion formulas. Bidirectional - type in …
OpenAngle Converter
Convert any angle to seven other units in one shot: degrees, radians, gradians, arcminutes, arcseconds, turns, and milliradians.
OpenArea Converter
Switch between nine common area units in one click: square metres, square feet, acres, hectares, square miles, and more.
OpenAres to Hectares Converter
Switch between ares and hectares with the exact 1:100 metric ratio. Used in European land registries, agricultural records, and garden-plot …
OpenAstronomical Unit (AU) Converter
The astronomical unit is the standard yardstick for distances inside our solar system. The IAU fixed 1 AU at exactly 149,597,870,700 metres …
OpenATM Pressure Conversion
Convert between the eight common pressure units anchored on the standard atmosphere. 1 atm is fixed at exactly 101,325 Pa.
OpenBarometric Pressure Conversion
Switch between the seven units used in weather, aviation, and meteorology. Standard atmosphere is 1013.25 hPa or 29.92 inHg.
OpenBinary Converter
Switch any number between binary, octal, decimal, and hexadecimal. Built on BigInt for unlimited size; useful for byte arithmetic, IP masks,…
OpenBinary to Hexadecimal Converter
Convert binary numbers to hexadecimal (and back) using the standard 4-bit nibble method. One hex digit equals exactly four bits, so 11010110…
OpenBinary to Octal Converter
Convert binary numbers to octal (and back) using 3-bit grouping. Each octal digit represents exactly three bits. The binary 111101101 maps t…
OpenCapacitance Conversion Calculator
Convert capacitance between farads (F), millifarads (mF), microfarads (μF), nanofarads (nF), and picofarads (pF) using exact SI prefix facto…
OpenCCF to Gallons Converter
Convert CCF (centum cubic feet, 100 ft³) to US gallons, imperial gallons, liters, or cubic meters. 1 CCF equals exactly 748.052 US gallons -…
OpenCCF to Therms Converter
Convert CCF (100 cubic feet of natural gas) to therms using the local heating value. The US national average is 1 CCF = 1.038 therms; region…
OpenCent to Square Meter Converter
Convert cent (the Indian land area unit used in Kerala, Tamil Nadu, Karnataka, and Andhra Pradesh) to square meters and back. 1 cent equals …
OpenCentigrade to Celsius Converter
Centigrade and Celsius are the same temperature scale - the CGPM officially renamed centigrade to Celsius in 1948. This tool shows the ident…
OpenCents to Euros Converter
Convert euro cents to euros (and back). 100 cents = 1 EUR exactly. The euro is legal tender in 20 European Union countries plus Andorra, Kos…
OpenCGS System of Units Converter
Convert between CGS (centimeter-gram-second) and SI (meter-kilogram-second) units across 11 physical quantities: force, energy, pressure, ma…
OpenCM to KM Converter
Convert centimeters to kilometers (and back) using the SI prefix system. 1 km = 1,000 m = 100,000 cm exactly. The conversion is a fixed fact…
OpenColor Converter (HEX, RGB, HSL, CMYK)
Convert any color between HEX, RGB, HSL, HSV, CMYK, and decimal formats in one click. Live swatch preview, color picker, and CSS-ready snipp…
OpenCoordinates Converter
Convert geographic coordinates between three standard formats: DMS (degrees-minutes-seconds), DD (decimal degrees), and DDM (degrees-decimal…
OpenCPS to Hz Converter
Convert cycles per second (CPS) to Hertz, kilohertz, megahertz, gigahertz, RPM, and radians per second. CPS and Hz are mathematically identi…
OpenCrore to Lakh Converter
Convert between crore and lakh in the Indian numbering system. 1 crore equals 100 lakh or 10 million. Useful for Indian property prices, sal…
OpenCubic Meter to Ton Converter
Convert cubic meters to metric or US short tons. Built-in densities for water, sand, gravel, concrete, asphalt, soil, crushed stone, and mor…
OpenCubic Yards to Tons Converter
Convert cubic yards to US short tons (or metric tons) for landscaping, hardscape, and bulk-aggregate jobs. Built-in densities for gravel, sa…
OpenDay Converter - Days to Hours, Weeks, Years
Convert days to all common time units in one widget - hours, minutes, seconds, weeks, months, years. Uses the exact 86,400 s/day and Gregori…
OpendBm to Watts Converter (RF Power)
Convert RF power between dBm and watts (and back). Standard tool for WiFi RSSI, cellular link budgets, Bluetooth class power, and ham radio.…
OpenDecagram to Gram Converter
Convert mass between decagrams and grams. The decagram (dag, dkg) equals exactly 10 grams and is the default unit at Polish bakeries, butche…
OpenDecimal to Hexadecimal Converter
Convert non-negative integers between decimal (base 10) and hexadecimal (base 16). Toggle case, add the 0x or # prefix, and see the binary a…
OpenDecimal to Octal Converter
Convert non-negative integers between decimal (base 10) and octal (base 8). Output also shows binary and hexadecimal. Optional 0o prefix in …
OpenDecimeter Conversion Calculator
Convert decimetres to and from any common length unit. 1 dm = 10 cm = 0.1 m = 3.937 in. Also covers the dm³ = 1 litre volume bridge.
OpenDegrees Minutes Seconds (DMS) Converter
Convert latitude or longitude between degrees-minutes-seconds and decimal degrees with hemisphere handling. Output includes arcminutes, arcs…
OpenDegrees to Minutes Converter
Convert plane angles between degrees and arcminutes with the exact factor 60. Standard unit for navigation charts, astronomical catalogs, su…
OpenDegrees to Radians Converter
Convert angles between degrees and radians with the exact factor π/180. Required for trigonometry, calculus, physics, and any graphics or ga…
OpenDegrees to Seconds (Arcseconds) Converter
Convert plane angles between degrees and arcseconds with the exact factor 3,600. Used for star catalogs, telescope resolution, geodetic surv…
OpenDensity Converter - kg/m³, g/cm³, lb/ft³
Convert material density between SI (kg/m³, g/cm³) and US units (lb/ft³, lb/gal, oz/in³). Quick presets for water, ice, common metals, and m…
OpenDimensional Analysis Calculator
Convert any value with the factor-label (dimensional analysis) method. Six quantity types, 40+ units, SI base units, and the full conversion…
OpenDistance Converter
Convert distance between 10 units: metric (mm, cm, m, km), imperial (in, ft, yd, mi), nautical miles, and light-years. Bidirectional with ex…
OpenEnergy Conversion Calculator
Convert energy between 9 units — joule, kilojoule, calorie, kilocalorie, BTU, kilowatt-hour, electronvolt, erg, foot-pound-force. Exac…
OpenFeet Converter
Convert feet between metres, centimetres, inches, yards, miles, and millimetres. 1 ft = 0.3048 m (1959 treaty). Auto feet-and-inches output.
OpenForce Conversion Calculator
Convert force between 10 units — newtons, kilonewtons, pounds-force, kilograms-force, dynes, kips, poundals. Uses CGPM standard gravit…
OpenGaj to Square Yard Converter
1 gaj equals exactly 1 square yard, which equals 9 square feet or 0.836 m². The traditional Indian land unit, still used in Delhi, Punj…
OpenGematria Calculator
Calculate the gematria value of any Hebrew or English text. Four cipher systems: Hebrew Standard (Mispar Hechrechi), Hebrew Ordinal (Siduri)…
OpenGreek Gematria (Isopsephy) Calculator
Compute the Greek isopsephy (gematria) value of any word: alpha=1, beta=2, ..., omega=800, sampi=900. Strips accents automatically. Includes…
OpenHex to RGB Converter
Convert any hex color code to R, G, B values (0-255). Live color preview, channel bars, plus HSL and CMYK output. Supports #RGB, #RRGGBB, an…
OpenHour Converter
Convert hours into minutes, seconds, milliseconds, days, weeks, decimal hours, and HH:MM:SS format. Type any hour value and see every common…
OpenImperial Unit Converter
Convert between imperial units and metric units across length, mass, and volume. Bidirectional, exact 1959 yard-and-pound factors, US and UK…
OpenKatha to Square Feet Converter
Convert Katha land area to square feet, square meters, acres, hectares, and bigha. Region-aware: West Bengal and Bangladesh use 720 sq ft; B…
OpenkPa Conversion Calculator
Convert kilopascals (kPa) to and from psi, bar, atm, mmHg, MPa, Pa, inHg, and mbar. SI pressure unit conversion for engineering, tire pressu…
OpenKSI to MPa Conversion Calculator
Convert between ksi (kilopounds per square inch) and MPa (megapascals) with the exact 6.894757 factor. Steel grades, yield strength, tensile…
OpenLand Area Converter
Convert land area between acres, hectares, square meters, square feet, square yards, square kilometers, square miles, and ares. One input, a…
OpenLat/Long to UTM Converter
Convert WGS84 geographic coordinates to UTM (Universal Transverse Mercator). Outputs easting, northing, zone, hemisphere, central meridian, …
OpenLeet Speak (1337) Converter
Translate normal text into leet speak (1337) and back. Choose basic (4-letter substitutions), intermediate (10 letters), or advanced (full a…
OpenLot Size to Square Feet Converter
Convert lot size to square feet from acres, square yards, square meters, or hectares. Also accepts length × width for rectangular lots. Comm…
OpenMesh to Micron Converter
Convert between sieve mesh number and micron (µm) opening using ASTM E11, Tyler, or ISO 3310-1 standards. 100 mesh equals roughly 149 µm; 40…
OpenMeter Conversion Calculator
Convert meters into any length unit - metric (km, cm, mm, µm, nm), imperial (ft, in, yd, mi), and nautical miles. Based on the 1983 SI defin…
OpenMetric System Converter
Universal metric converter for length. Every SI prefix from kilo (10³) down to nano (10⁻⁹) - kilometers, hectometers, dekameters, decimeters…
OpenMicrometer Conversion (µm)
Convert between micrometers (µm) and millimeters, centimeters, meters, nanometers, mils, or inches. 1 µm = 10⁻⁶ m by SI definition. Used in …
OpenMicron to Mil Converter
Convert between microns (µm) and mils (thou). 1 mil = 0.001 inch = 25.4 µm exactly. The industry standard for coating thickness, film gauge,…
OpenMil Conversion Calculator
Convert mils - thousandths of an inch - to micrometers, millimeters, centimeters, inches, meters, or nanometers. 1 mil = 25.4 µm exactly. Li…
OpenMillimeter Converter (mm)
Convert millimeters into metric (cm, m, km, µm) and imperial (in, ft, yd, mil) length units. 1 mm = 1/25.4 inch by exact definition. Enginee…
OpenMinute Converter
Convert minutes between any common time unit: seconds, milliseconds, hours, days, weeks, months, years. Based on SI second definition (cesiu…
OpenMinutes to Decimal Hours Converter
Convert minutes to decimal hours for payroll, billing, and time tracking. 60 min = 1.0 h, 15 min = 0.25 h, 6 min = 0.1 h. Used by HR systems…
OpenmmHg to Atm Converter
Convert pressure between mmHg (millimeters of mercury, also called torr) and atm (standard atmosphere). 1 atm = 760 mmHg exactly. Used in me…
OpenMPa Conversion Calculator
Convert megapascals to seven engineering pressure units with exact factors. Used for concrete strength, hydraulic pressure, and structural s…
OpenMPa to PSIG Converter
Convert megapascals to pounds per square inch gauge (psig) with the proper 14.696 psi atmospheric offset. PSIG vs PSIA explained, with chart…
OpenNanometer Converter (nm)
Convert nanometers to six target length units with exact SI factors. Useful for visible-light wavelength, semiconductor process nodes, and m…
OpenNatural Gas Unit Converter
Convert natural gas between volume and energy units. Uses 1 ccf ≈ 1.037 therm at the U.S. EIA standard heat content. Bidirectional with seve…
OpenOunces to Cups Converter
Convert fluid ounces (fl oz) to cups and back. Supports US customary, US legal, metric, imperial, and Japanese cup sizes with fraction displ…
OpenPaper Quantity Converter
Convert paper between sheets, quires, reams, bundles, and bales. Uses the 25/500/1000/5000 trade-standard sheet counts. Bidirectional with f…
OpenPascal Conversion Calculator
Convert pascals to nine pressure units. Pascal is the SI unit (1 N/m²); the converter covers metric, imperial, traditional, and laboratory u…
OpenPower Conversion Calculator
Convert watts to nine power units: kilowatt, megawatt, three horsepower variants, BTU per hour, calorie per second, foot-pound per second, a…
OpenPressure Converter
Convert between all major pressure units. Bar as base for industrial convenience, but bidirectional with ten target units covering metric, i…
OpenPressure Unit Conversion
Convert pressure between 11 different units using pascal as the SI base. Explains gauge versus absolute pressure, fluid statics, and depth-p…
OpenPSI Conversion Calculator
Convert pressure between PSI and bar, kPa, MPa, atm, mmHg, inHg and kg/cm². Uses the exact PSI definition (6894.757293 Pa) for engineering-g…
OpenPSI to GPM Calculator
Calculate water flow rate (GPM) from pressure (PSI) using a valve flow coefficient Cv or a fire-sprinkler K-factor. Includes the NFPA 13 spr…
OpenPX to EM Converter
Convert CSS pixels to em, rem, points and percent using a configurable base font-size (default 16 px). Built for responsive typography and W…
OpenQuantity Converter (Dozen / Gross / Score)
Convert between dozen (12), score (20), gross (144), great gross (1728), baker's dozen (13), pair (2) and ream (500). Useful for wholesale b…
OpenRadians to Degrees Converter
Convert angles between radians and degrees instantly. Uses the exact 180/π factor. 1 rad = 57.2958°, π rad = 180°, 2π rad = 360°. Built for …
OpenRadiation Converter (Sv, Rem, Gy, Bq, Ci)
Convert ionising radiation units: equivalent dose (Sv, mSv, µSv, rem, mrem), absorbed dose (Gy, mGy, rad), and activity (Bq, kBq, MBq, GBq, …
OpenRMS to Watts Calculator
Calculate real (RMS) power in watts from RMS voltage, current, impedance or all three with power factor. Built for audio amplifier sizing, A…
OpenRoman Numerals Converter
Convert numbers between Arabic (1-3999) and Roman numerals using standard subtractive form (IV, IX, XL, XC, CD, CM). Built for dates, chapte…
OpenScale Conversion Calculator
Convert between drawing/model dimensions and real-world dimensions for any ratio scale (1:24, 1:48, 1:87 HO, 1:100, 1:160 N, 1:200, 1:500, 1…
OpenSeconds Converter (sec to min, hr, day, year)
Convert seconds to and from milliseconds, microseconds, nanoseconds, minutes, hours, days, weeks and years (365.25 days). Includes HH:MM:SS …
OpenSpeed Converter
Convert speed across all common units - metric, imperial, nautical, aviation, and relativistic. Uses exact SI factors with m/s as the base u…
OpenSquare Centimeters to Square Millimeters Converter
Convert area between square centimeters and square millimeters. The linear cm-to-mm factor is 10, so the area factor squares to 100. Used fo…
OpenSquare Feet Converter
Convert area between square feet and metric/imperial units - m², yd², in², acres, hectares, km². Built around the exact 0.09290304 factor fr…
OpenSquare Yard Converter
Convert area between square yards and metric or other imperial units. Used for carpet, sod, landscaping, and US/UK real estate. Built on exa…
OpenTime Unit Converter
Convert any time interval across 12 units, from nanoseconds to centuries. Uses SI seconds as the base, the tropical year (365.2425 days) for…
OpenUniversal Measurement Converter
Universal measurement converter covering length, weight, volume, area, speed, time, and temperature. Bidirectional conversion between SI and…
OpenUniversal Unit Conversion Calculator
One conversion calculator for length, weight, volume, temperature, area, speed, and time. Built-in support for metric, imperial, US, and UK …
OpenUnix Time Converter
Convert between Unix timestamps (seconds since 1970-01-01 UTC) and human-readable dates. Outputs UTC, local time, ISO 8601, milliseconds, da…
OpenUppercase to Lowercase Converter
Convert text between every common case format - UPPERCASE, lowercase, Title Case, Sentence case, tOGGLE cASE. Live counts of characters, wor…
OpenVolume Conversion Calculator
Convert any volume unit to any other: liters, milliliters, m³, US/UK gallons, quarts, pints, cups, fluid ounces, tablespoons, teaspoons, ft³…
OpenNo calculators match .