Unit Converter
Convert common metric and imperial measurements for length, weight, temperature, volume and speed. Built for everyday UK conversions like cm to inches, kg to stone, litres to pints and mph to km/h.
Convert units
Choose a category, enter a value and select the units to convert between. Temperature uses its own formula; other categories use conversion factors.
Popular everyday conversions
Use these quick buttons to load common UK conversions into the calculator.
How unit conversion works
Most measurement conversions use a conversion factor. You multiply or divide by a fixed number to change from one unit to another.
converted value = original value × conversion factorFor example, 1 inch is exactly 2.54 centimetres, so centimetres can be divided by 2.54 to get inches.
inches = centimetres ÷ 2.54
centimetres = inches × 2.54UK metric and imperial notes
The UK often mixes metric and imperial measurements in everyday life. Road speeds are usually shown in miles per hour, body weight is often spoken about in stone and pounds, and food packaging is usually metric.
- Length: centimetres, metres, inches, feet, yards and miles.
- Weight: grams, kilograms, ounces, pounds and stone.
- Volume: millilitres, litres, teaspoons, tablespoons, UK pints and UK gallons.
- Temperature: Celsius, Fahrenheit and Kelvin.
- Speed: mph, km/h, metres per second and knots.
Example conversions
| Conversion | Approximate result | Useful for |
|---|---|---|
| 10 cm to inches | 3.94 inches | Product sizes, screens, small measurements |
| 5 miles to kilometres | 8.05 km | Travel, running, distances |
| 70 kg to stone | 11.02 stone | Body weight comparisons |
| 2 litres to UK pints | 3.52 pints | Drinks, liquids and household quantities |
| 70 mph to km/h | 112.65 km/h | Driving and travel comparisons |
FAQs
How do you convert units?
Most units are converted by multiplying by a conversion factor. For reverse conversions, divide by the same factor.
What is the difference between metric and imperial?
Metric units include metres, grams and litres. Imperial units include inches, feet, pounds, stone, pints and gallons.
Why does temperature conversion look different?
Celsius and Fahrenheit do not share the same zero point, so they need a formula rather than a simple multiplication factor.
Can I use this for cups to grams?
Not directly. Cups are volume and grams are weight, so the answer depends on the ingredient. Use the cooking unit converter for food-specific cup-to-gram estimates.