Unit ConverterFast, Free & Accurate
Convert between 818+ unit combinations instantly. Length, weight, volume, temperature, and more โ all in one place.
Unit Categories
Choose a category to start converting
Length
Convert between metric and imperial length units including meters, feet, inches, kilometers, and miles.
Weight & Mass
Convert between metric and imperial weight/mass units including kilograms, pounds, ounces, and tonnes.
Volume
Convert between volume units including liters, gallons, cups, fluid ounces, and cubic meters.
Temperature
Convert between temperature scales including Celsius, Fahrenheit, Kelvin, and Rankine.
Area
Convert between area measurement units including square meters, acres, hectares, and square feet.
Speed
Convert between speed and velocity units including km/h, mph, m/s, knots, and Mach.
Pressure
Convert between pressure units including Pascal, bar, PSI, atmosphere, and mmHg.
Energy
Convert between energy units including joules, calories, kilowatt-hours, BTU, and electronvolts.
Power
Convert between power units including watts, kilowatts, horsepower, and BTU per hour.
Digital Storage
Convert between digital storage units including bytes, kilobytes, megabytes, gigabytes, and terabytes.
Time
Convert between time units including seconds, minutes, hours, days, weeks, months, and years.
Frequency
Convert between frequency units including Hertz, kilohertz, megahertz, gigahertz, and RPM.
Fuel Economy
Convert between fuel economy units including MPG, km/L, and L/100km.
Angle
Convert between angle units including degrees, radians, gradians, and arc minutes.
Popular Conversions
Most searched unit conversions worldwide
Free Online Unit Converter
UnitConverter.pro is a free, comprehensive unit conversion tool that helps you convert between metric and imperial units instantly. Whether you need to convert centimeters to inches, kilograms to pounds, Celsius to Fahrenheit, or any other unit โ our calculator provides instant, accurate results.
Supported Unit Categories
Our converter supports 14 categories with over 818 conversion combinations, including:
- Length: Nanometers, Micrometers, Millimeters, Centimeters, Meters, Kilometers, Inches, Feet, Yards, Miles, Nautical Miles, Fathoms
- Weight & Mass: Micrograms, Milligrams, Grams, Kilograms, Metric Tons, Ounces, Pounds, Stones, US Tons, Imperial Tons
- Volume: Milliliters, Liters, Cubic Meters, Cubic Inches, Cubic Feet, Teaspoons, Tablespoons, Fluid Ounces, Cups, Pints, Quarts, US Gallons, Imperial Gallons
- Temperature: Celsius, Fahrenheit, Kelvin, Rankine
- Area: Square Millimeters, Square Centimeters, Square Meters, Square Kilometers, Square Inches, Square Feet, Square Yards, Square Miles, Acres, Hectares
- Speed: Meters per Second, Kilometers per Hour, Miles per Hour, Feet per Second, Knots, Mach
- Pressure: Pascals, Kilopascals, Megapascals, Bars, Atmospheres, PSI, mmHg, Torr
- Energy: Joules, Kilojoules, Calories, Kilocalories, Watt-hours, Kilowatt-hours, BTU, Electronvolts, Foot-pounds
- Power: Watts, Kilowatts, Megawatts, Horsepower, BTU per Hour, Foot-pounds per Second
- Digital Storage: Bits, Bytes, Kilobytes, Megabytes, Gigabytes, Terabytes, Petabytes
- Time: Milliseconds, Seconds, Minutes, Hours, Days, Weeks, Months, Years
- Frequency: Hertz, Kilohertz, Megahertz, Gigahertz, RPM
- Fuel Economy: Kilometers per Liter, Miles per Gallon, Miles per Gallon (UK), Liters per 100km
- Angle: Degrees, Radians, Gradians, Arc Minutes, Arc Seconds
How to Use
Simply select a category, choose your source and target units, enter a value, and get an instant conversion. Each conversion page includes a reference table with common values, the conversion formula, and frequently asked questions.