Unit Converter
Convert length, mass, temperature, area, volume and speed, with explicit metric, US and Imperial units.
Convert length between explicitly named units.
Result
Metres → Kilometres. US and Imperial volume units are explicitly distinct. Display precision is limited; internal conversion retains additional digits.
How to use this calculator
Convert length between explicitly named units. Enter amounts in the units shown, select the applicable options, and click Calculate. Use Reset to restore the starting values.
Calculation formula
Base value = input × source factor + source offset; output = (base value − target offset) / target factor.
Assumptions and accuracy
Check the selected mode, units, date endpoints and result notes. Currency selection controls display and rounding, not exchange rates. Calendar calculations do not include holidays or local time-of-day.
Choose what to calculate
Celsius to Fahrenheit calculator
Convert supported temperature, length, mass, area, volume and speed units. US and Imperial volume units are distinguished explicitly.
Open this calculationUnderstanding this calculation
Convert a value within one of six categories: length, mass, temperature, area, volume or speed. Unit names identify metric, US and Imperial quantities explicitly so similarly named units are not treated as interchangeable.
Worked examples
Convert one metre to centimetres
Use the explicitly stated inputs; the example link fills them in.
- One centimetre is 0.01 metre.
- 1 / 0.01 = 100 centimetres.
One metre equals 100 centimetres.
Try these inputsConvert water’s freezing point between temperature scales
Use the explicitly stated inputs; the example link fills them in.
- Celsius = (Fahrenheit − 32) × 5 / 9.
- (32 − 32) × 5 / 9 = 0.
32 degrees Fahrenheit equals 0 degrees Celsius.
Try these inputsCommon questions
Are US gallons and Imperial gallons equal?
No. One US liquid gallon is 3.785411784 litres; one Imperial gallon is 4.54609 litres. Select the correct named unit.
Why is temperature conversion different from length conversion?
Temperature scales may have different zeros as well as different unit sizes. The converter applies both the scale factor and offset.
Scope and assumptions
Conversions use stated unit definitions and retain floating-point precision internally, with limited display precision. Units from different dimensions cannot be mixed. Temperatures below absolute zero are rejected.
Sources
Calculation notes checked . Examples are mathematical checks under the stated assumptions.
Calculation methods and formulas
Length
Convert length between explicitly named units.
Base value = input × source factor + source offset; output = (base value − target offset) / target factor.
Mass
Convert mass between explicitly named units.
Base value = input × source factor + source offset; output = (base value − target offset) / target factor.
Temperature
Convert temperature between explicitly named units.
Base value = input × source factor + source offset; output = (base value − target offset) / target factor.
Area
Convert area between explicitly named units.
Base value = input × source factor + source offset; output = (base value − target offset) / target factor.
Volume
Convert volume between explicitly named units.
Base value = input × source factor + source offset; output = (base value − target offset) / target factor.
Speed
Convert speed between explicitly named units.
Base value = input × source factor + source offset; output = (base value − target offset) / target factor.
See our calculation methodology and review status for data versions, rounding and validation limitations.