Unit converters
546 unit converters: length, weight, temperature, volume, speed, pressure, energy, data and cooking measures. Type a value, pick the units and get an exact result with the conversion factor shown, free in your browser.
Roman numeral converter
Switch between ordinary numbers and Roman numerals in both directions: 2026 becomes MMXXVI, and MMXXVI reads back as 2026.
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Decibel ratio converter
A power ratio of 2 is about 3 dB. Pick power or amplitude, enter a linear ratio or a dB level, and get both forms with the right factor: 10 for power, 20 for…
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Electrical conductivity converter
1.5 S/m is 0.015 S/cm, and confusing the two shifts a reading by a factor of 100. Convert conductivity between siemens or mho per metre, centimetre and…
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Convert equivalent dose
One sievert equals 100 rem, and one millisievert is 1000 microsieverts. Convert equivalent dose between Sv, mSv, µSv and rem so old badge reports, monitor logs…
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HP to kW converter
100 hp is 74.569987158227 kW: type the horsepower from an engine, pump or motor nameplate and get kilowatts with the exact factor, plus the watts, ready for…
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Length converter
Change one measurement into another unit in a single step: 5 kilometers come out as 3.106855961187 miles.
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Convert mass moment of inertia
Convert mass moment of inertia between kg·m², g·cm² and lb·ft²: 1 kg·m² is 10000000 g·cm². Line up a European motor datasheet, a micro-gear catalogue and a US…
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Pressure gradient converter
The freshwater benchmark of 0.433 psi per foot is 9794.7175457411 pascals per meter. Convert pressure gradients between oilfield and metric units for…
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Stone to lbs converter
12 stone is exactly 168 pounds, because one stone is 14 lb. Turn a UK or Irish body weight in stone into the pounds that US apps, gym forms and shipping labels…
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Temperature converter
One converter for the four temperature scales: 100 °C is 212 °F, and every result is checked against absolute zero so an impossible reading never reaches your…
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Octal to decimal converter
Octal 755 is 493 in decimal, and a mode written as 0755 gives the same answer. Every digit is checked to be 0 to 7 before anything is calculated, so a stray 8…
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Cardinal to ordinal number converter
21 becomes 21st, and the tricky teens stay right: 11th, 12th and 13th, never 11st. One rule set for rankings, race results, certificates and product copy, with…
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EMC field strength converter
1 V/m is 120 dBµV/m, the scale EMC labs report in. Convert field strength between volts per metre and its prefixed forms, the dBµV/m, dBmV/m and dBV/m log…
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Absorbed dose converter
1 gray is exactly 100 rad: the converter passes every dose through grays to move between Gy, mGy, rad and erg/g, so old rad charts, imaging reports and…
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Acceleration converter
9.80665 m/s² is exactly 1 g: the converter links m/s², ft/s², standard gravity and the gal through one exact SI bridge, then shows your value in all four units…
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Mole unit converter
1 mole is 1,000 millimoles, and one pound-mole is exactly 453.59237 moles. Convert an amount of substance between mol, mmol, µmol, kmol and lb-mol, and see the…
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Angle converter
180 degrees are π radians, or 3.14159265359. Convert angles between degrees, radians, gradians, arcminutes, arcseconds and turns, with the value in radians and…
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Angular acceleration converter
1 rad/s² equals 57.2957795131 deg/s² and 572.957795131 rev/min². This converter handles rotational, not straight-line, acceleration and shows your value in all…
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Angular velocity converter
60 RPM is 6.2831853072 rad/s, one full turn every second. Convert rotation rates between rad/s, deg/s, RPM and revolutions per second, so a motor nameplate, a…
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Area converter
100 square metres are 1,076.391041671 square feet. Convert any area between m², ft², acres, hectares, square miles and km² with fixed international factors, so…
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Astronomical distance converter
Light-years, parsecs and astronomical units in one converter: 1 AU is 149,597,870.7 km, and every value passes through exact definitions, so solar-system…
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Blood glucose converter
100 mg/dL is 5.5499439456 mmol/L: the converter divides or multiplies by the clinical constant 18.0182, so a reading from a US meter and a European lab report…
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Bra size converter
A US 34C is a 75C in Europe, a 90C in France and a 12C in Australia. Type one size and see its label in all five systems, with cups after D matched by volume…
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Capacitance converter
One microfarad is 1,000,000 picofarads. Convert any capacitance between farads, millifarads, microfarads, nanofarads and picofarads and see the value in all…
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Catalytic activity converter
One microkatal equals 60 enzyme units (U). Convert catalytic activity between katals, microkatals, nanokatals and enzyme units, with the step through katals…
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Cholesterol unit converter
200 mg/dL of total cholesterol is about 5.17 mmol/L. Convert total, HDL or LDL cholesterol between US milligrams per decilitre and SI millimoles per litre with…
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Clothing size converter
A US women's 8 is a UK 12 and an EU 38. Enter a size and its system to get the matching US, UK, EU and S/M/L labels from a fixed international chart, for…
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Molar concentration converter
1 mol/L is 1,000 mmol/L: convert molar concentrations between mol/L, mmol/L, µmol/L and mol/m³ so lab reports, kit inserts and SI engineering datasheets can be…
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Conductance converter
1 millisiemens is 1,000 microsiemens: convert electrical conductance between siemens, millisiemens, microsiemens and mhos, and see the same value in all four…
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Data transfer rate converter
100 Mbps is 12.5 MB/s: convert bandwidth between bits, kilobits, megabits and gigabits per second and bytes or megabytes per second, so an ISP plan, speed test…
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Digital storage converter
1,024 bytes are exactly 1 KiB: convert file and memory sizes between bytes, KB, MB, GB and TB in powers of 1,000 and KiB, MiB, GiB and TiB in powers of 1,024…
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Density converter
1000 kg/m³ is exactly 1 g/cm³. Enter a density in kg/m³, g/cm³, lb/ft³ or pounds per US gallon and read the same value in all four units at once, for lab…
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Dynamic viscosity converter
One pascal-second is 1000 centipoise. Convert dynamic viscosity between pascal-seconds, poise, centipoise and pound-force seconds per square foot for fluid…
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Electric charge converter
One coulomb is 1000 millicoulombs. Convert charge between coulombs, millicoulombs, microcoulombs, ampere-hours, milliampere-hours and elementary charges, so…
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Electric current converter
One kiloampere is 1000 amperes, and one microampere is a millionth of an ampere. Convert current between amperes, milliamperes, microamperes, kiloamperes and…
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Electric field strength converter
One volt per mil is about 39370 volts per metre, because a mil is a thousandth of an inch. Convert field strength between V/m, V/cm, kilovolts per metre and…
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Energy converter
One kilowatt-hour is 3,600,000 joules, and one food Calorie is 4184 joules. Convert energy between joules, kilojoules, calories, kilocalories, watt-hours…
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Fahrenheit to Celsius converter
Turn a US weather, thermostat or oven reading in Fahrenheit into Celsius with the exact formula: 32 °F is 0 °C and 212 °F is 100 °C, without the…
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Volume flow rate converter
Switch a flow rate between L/s, m³/h, US gallons per minute and cubic feet per minute: 1 L/s is 15.850323141489 gpm.
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Force converter
Switch a force between newtons, kilonewtons, dynes, pounds-force, kilograms-force and poundals: 1 lbf is 4.4482216152605 N, worked out through newtons with…
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Frequency converter
Switch a frequency between Hz, kHz, MHz, GHz, RPM and radians per second: 1000 Hz is 1 kHz, and every conversion runs through hertz with fixed factors.
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Frequency wavelength converter
Find the wavelength of any frequency, or the reverse, with wavelength equal to speed divided by frequency. In vacuum, 300,000,000 Hz gives 0.9993081933 m.
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Fuel economy converter
Restate a fuel economy figure on the scale your market uses: 30 US MPG is 7.84048611111 L/100km, 12.7543112229 km/L or 36.0284977651 UK MPG, all shown together.
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Fuel price unit converter
Restate a pump price per US gallon, per imperial gallon or per liter: 3.5 per US gallon is 0.924602183254 per liter in the same currency, because one US gallon…
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Grain weight converter
One grain is exactly 64.79891 milligrams, so a 100-grain powder charge weighs 6.479891 grams. Move any weight between grains, grams, milligrams and avoirdupois…
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Hat size converter
A US 7 fitted hat is a UK 6 7/8, a European 56 and a head of 56 cm, about 22.05 inches. Enter the size you know in any of those systems and see the others in…
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Heat flux density converter
A heat flux of 1000 W/m² is about 317 BTU per hour per square foot, or 0.1 W/cm². Enter one value and see it in all four units at once, for building envelopes…
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Heat transfer coefficient converter
A film coefficient of 1 W/(m²·K) is 0.1761101837 BTU/(h·ft²·°F), and 1 BTU/(h·ft²·°F) is 5.6782633412 W/(m²·K).
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Illuminance converter
500 lux is 46.45152 foot-candles: move a light level between lux, foot-candles, phot and lumens per square metre when an office standard, an old facilities…
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Inductance converter
1 henry is 1000 millihenries: move an inductance between H, mH, µH, nH and pH while you read a coil datasheet, a PCB inductor catalog, an RF matching note or a…
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Gold karat converter
18 karat gold is 750 fineness and 75 percent pure: enter a purity on any of the three scales and see the other two at once, for reading hallmarks, pricing scrap…
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Kinematic viscosity converter
Convert kinematic viscosity between m²/s, stokes, centistokes and ft²/s and see all four at once: 1 m²/s equals 10000 stokes or 1000000 centistokes.
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Luminance converter
Compare screen and projector brightness across old and modern units: 100 nits equal 29.186350796 foot-lamberts.
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Luminous flux converter
Move a lumen figure to the prefix your datasheet uses: 800 lumens are 0.8 kilolumens. Five flux units, from microlumens to megalumens, for LED packages, product…
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Luminous intensity converter
Put an LED's millicandela rating and a lamp's candlepower on the same scale: 1 candela is 1000 millicandela, and one candlepower counts as one candela.
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Magnetic flux converter
Move magnetic flux between SI and old CGS units in one step: 1 weber is exactly 100,000,000 maxwell.
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Magnetic flux density converter
Switch a magnetic field reading between SI and CGS: 1 tesla is exactly 10,000 gauss and 10,000,000 milligauss.
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Mass converter
Enter a weight once and see it in seven units: 1 kilogram is 2.20462262185 pounds, 35.2739619496 ounces and 1000 grams.
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Mass flow rate converter
Read a mass throughput in the unit your datasheet uses: 1 kg/s is 7936.641438655593 pounds per hour.
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Molar mass converter
Convert molar mass between g/mol, kg/mol and kg/kmol: water's 18.015 g/mol is also 18.015 kg/kmol, while 1 kg/mol is 1000 g/mol.
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