Unit converter
Convert lengths, weights, power and more
Runs in your browser. Nothing is sent unless you share it.
1 m =
100 cm
How this is calculated
Each unit converts through the base unit of its group using exact definitions, for example 1 inch = 25.4 mm. Temperatures convert through kelvin, fuel economy through litres per 100 km, and electrical power with P = V × I × power factor (× √3 for three phase).
How it works
- Pick a preset, such as Electrician, Plumber, HVAC or Carpenter, or show every category.
- Choose the category, then the units to convert from and to, and type the value.
- Most units convert through a base unit: result = value × factor of the first unit ÷ factor of the second. Temperature and fuel economy use their own formulas.
- For watts, amps and volts, enter the third quantity and the power factor: P = V × I × PF, or P = √3 × V × I × PF on three phase.
Related tools
Questions
How do I convert watts to amps?
Divide the watts by the voltage, and by the power factor if it is below 1. A 2,300 W heater on 230 V draws 10 A. On three phase, divide by √3 as well.
How do I convert Celsius to Fahrenheit?
Multiply by 9, divide by 5 and add 32. So 40 °C is 104 °F. The tool refuses temperatures below absolute zero.
How do AWG wire sizes compare with mm²?
A smaller AWG number is a thicker wire. 12 AWG is about 3.31 mm² and 10 AWG about 5.26 mm². The tool shows a table of common sizes.
Why is fuel economy treated differently?
Litres per 100 km rise as a car uses more fuel, while km per litre and miles per gallon fall, so they are converted by division. US and UK gallons also differ in size.
Where do my values go?
Runs in your browser. Nothing is sent unless you share it.