Free Online Unit Converter

Convert length, mass, temperature, and 12 more categories. Enter a value to get started. No account needed.

Conversion Categories

Length

Convert length and distance units: meters, feet, inches, miles, km, yards, and more.

11 units available →

Mass

Convert mass and weight units: kilograms, pounds, ounces, grams, stones, and tons.

10 units available →

Temperature

Convert temperature between Celsius, Fahrenheit, Kelvin, and Rankine.

4 units available →

Area

Convert area units: sq feet, sq meters, acres, hectares, sq miles, and more.

10 units available →

Volume

Convert volume units: liters, gallons, cups, milliliters, fluid ounces, and more.

18 units available →

Speed

Convert speed units: mph, km/h, m/s, knots, Mach, and more.

7 units available →

Data Storage

Convert decimal and binary data units: bytes, KB, MB, GB, KiB, MiB, GiB, and bits.

16 units available →

Time

Convert time units: seconds, minutes, hours, days, weeks, months, and years.

12 units available →

Pressure

Convert pressure units: PSI, bar, Pascal, atm, mmHg, and more.

10 units available →

Energy

Convert between joules, calories, kilowatt-hours, BTU, and more energy units.

14 units available →

Angle

Convert between degrees, radians, gradians, arcminutes, arcseconds, and other angle units.

7 units available →

Frequency

Convert between hertz, kilohertz, megahertz, gigahertz, RPM, and other frequency units.

8 units available →

Density

Convert between kg/m³, g/cm³, lb/ft³, lb/in³, and other density units.

11 units available →

Fuel Economy

Convert between mpg (US/Imperial), L/100km, km/L, and other fuel economy units.

6 units available →

Data Transfer Rate

Convert data transfer rate units: bps, Kbps, Mbps, Gbps, KB/s, MB/s, GB/s.

10 units available →

Popular Conversions

Choose a conversion to see its formula and worked examples.

Feet to Centimetersft to cm Inches to Centimetersin to cm Kilometers to Mileskm to mi Meters to Feetm to ft Pounds to Kilogramslb to kg Ounces to Gramsoz to g Kilograms to Poundskg to lb Fahrenheit to CelsiusF to C Celsius to FahrenheitC to F Celsius to KelvinC to K Gallons to Litersgal to l Cups to Milliliterscup to ml Liters to Gallonsl to gal Miles per Hour to Kilometers per Hourmph to kph Kilometers per Hour to Miles per Hourkph to mph Square Feet to Square Metersft2 to m2 Acres to Hectaresacre to ha Megabytes to GigabytesMB to GB Gigabytes to TerabytesGB to TB Hours to Minutesh to min Days to Hoursd to h PSI to Barpsi to bar Atmospheres to Pascalsatm to Pa Kilocalorie → Kilojoulekcal to kJ Kilowatt-hour → MegajoulekWh to MJ BTU → JouleBTU to J Joule → CalorieJ to cal Degree → Radiandeg to rad Radian → Degreerad to deg Degree → Arcminutedeg to arcmin Hertz → KilohertzHz to kHz Megahertz → GigahertzMHz to GHz RPM → Hertzrpm to Hz g/cm³ → kg/m³g-cm3 to kg-m3 lb/ft³ → kg/m³lb-ft3 to kg-m3 kg/L → kg/m³kg-l to kg-m3 mpg(US) → L/100kmmpg-us to L100km L/100km → mpg(US)L100km to mpg-us mpg → km/Lmpg-us to km-l Megabits per Second to Megabytes per SecondMbps to MB-s Megabytes per Second to Megabits per SecondMB-s to Mbps Gigabits per Second to Megabytes per SecondGbps to MB-s Kilobits per Second to Megabits per SecondKbps to Mbps

How to Use Our Unit Converter

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Choose what you want to measure, such as length or temperature.

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All conversion factors are sourced fromNIST Special Publication 811and theBIPM SI Brochure (9th edition), and computed with arbitrary-precision arithmetic.