Why is temperature conversion different from the others?

Length and weight units are all proportional to each other (double the meters, double the feet), but 0°C isn't 0°F - each temperature scale has its own zero point, so converting requires shifting, not just scaling.

How precise are the results?

Conversions use standard, widely-accepted ratios (e.g. 1 inch = 2.54cm exactly) and round to a reasonable number of decimal places for readability.

Unit Converter

Convert between length, weight, and temperature units.

Value

Unit

Meters

1 m

Millimeters

1,000 mm

Centimeters

100 cm

Kilometers

0.001 km

Inches

39.370079 in

Feet

3.28084 ft

Yards

1.093613 yd

Miles

0.000621 mi

How it works

Length and weight conversions work by converting your value into a common base unit (meters, grams) and back out into the target unit - each unit's ratio to that base is fixed and known. Temperature is different: Celsius, Fahrenheit, and Kelvin don't share a common zero point, so converting between them uses a formula rather than a simple multiplication.

Read the full guide

How to use it

Pick a category - length, weight, or temperature.
Enter a value and choose the units to convert from and to.
The converted value updates instantly.

Examples

10 km6.21 mi

5 kg11.02 lb

100°C212°F

Frequently asked

Why is temperature conversion different from the others?: Length and weight units are all proportional to each other (double the meters, double the feet), but 0°C isn't 0°F - each temperature scale has its own zero point, so converting requires shifting, not just scaling.
How precise are the results?: Conversions use standard, widely-accepted ratios (e.g. 1 inch = 2.54cm exactly) and round to a reasonable number of decimal places for readability.

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