Choose a type of measurement, enter a value and pick the units to convert between. It covers length, weight, volume and temperature, and shows the reverse rate too.
Results are estimates for planning. Check the figures before you make a financial or health decision.
How the Unit converter works
Choose a measure (length, weight, volume or temperature), type a value and select the unit you are converting from and to.
For length, weight and volume, every unit is stored as a multiple of a base unit. The tool multiplies your value by the “from” factor and divides by the “to” factor:
result = value × (from factor ÷ to factor)
It also shows the reverse, such as 1 mile equalling a certain number of kilometres, so you can convert in your head next time.
Temperature cannot be done with a single factor because the scales start at different points. The tool first converts to Celsius, then to the target: Fahrenheit = °C × 9 ÷ 5 + 32, and kelvin = °C + 273.15.
Be careful with volume, since UK and US measures differ. A UK gallon is 4.54609 litres and a US gallon is 3.78541 litres, so pick the right one. Results are shown to up to six figures.
Worked example
Using the default values in the calculator above:
| Input | Value |
|---|---|
| Measure | Length |
| Value | 10 |
| From | Kilometres |
| To | Miles |
10 kilometres equals: 6.213712 miles
| Reverse | 1 miles = 1.609344 kilometres |
|---|
Tips and common mistakes
Check the “from” and “to” units before reading the answer, as swapping them is the most common mistake. For volume, make sure you choose UK or US units to match the source.
For cooking, volume-to-weight conversions depend on the ingredient, so use the Cooking conversions calculator instead. For oven temperatures, the Oven temperature converter calculator also converts gas marks. For land and room sizes, the Area and square footage calculator gives area in several units at once.
Frequently asked questions
How do I convert between metric and imperial?
Pick the measure, enter your value and choose the two units. The result and the reverse rate are shown straight away.
Are UK and US gallons the same?
No. A UK gallon is 4.54609 litres and a US gallon is 3.78541 litres. Choose the unit that matches your source.
How is temperature converted?
The value is first converted to Celsius, then to the unit you want, using the standard formulas for Fahrenheit and kelvin.