Unit Converter – Length, Weight, Volume and Temperature
Result
About Unit Converter
Convert between metric and imperial units across four everyday categories. Pick your units, type a value, and the result appears as you type — with a swap button to reverse the direction.
Most day-to-day conversion questions fall into a handful of categories: how far, how heavy, how much, how hot. This covers those four rather than burying them under dozens of specialist units you will never need.
Temperature works differently from the others and is worth understanding. Length, weight and volume are simple ratios — a kilometre is always 0.621 miles. Temperature scales have different zero points, so converting Celsius to Fahrenheit means multiplying and then adding an offset, which is why 0 degrees Celsius is 32 Fahrenheit rather than 0.
Worked examples
5 miles is about 8.047 km (5 × 1.609344). 10 pounds is about 4.536 kg. 1 ounce is 28.35 g, so 8 oz is about 227 g. For temperature, 100 °C is 212 °F, body temperature of 37 °C is 98.6 °F, and −40 is the one point where both scales read the same.
Temperature is different
Length, weight and volume convert by multiplying by a fixed factor, so converting there and back returns what you started with. Temperature needs a multiply and an offset: °F = °C × 9/5 + 32, and °C = (°F − 32) × 5/9. That is why doubling a temperature in Celsius does not double it in Fahrenheit, and why a 10 °C rise is 18 °F.
For quick mental estimates, double the Celsius figure and add 30: 20 °C gives about 70 °F (the exact figure is 68). It drifts at the extremes, so use the tool for anything that matters.
US and UK measures
Pints, gallons and fluid ounces differ between the US and the UK: a US pint is 473 ml and a UK pint is 568 ml. The volume units here follow the US system unless stated, so a UK recipe or a pint of beer converted with US values will be roughly 17 per cent off. If the source is British, check which pint or cup it means before relying on the result.
The converter gives well-rounded results, not laboratory precision. For engineering or scientific work that needs many significant figures, use the exact factor from your standard rather than a rounded display.
What you can use it for
- Convert a recipe from cups and ounces to grams and millilitres.
- Work out your height or weight in the other system for a form.
- Convert a distance from miles to kilometres while travelling.
- Translate a weather forecast between Celsius and Fahrenheit.
- Check a product listed in imperial units against a metric specification.
How it works, step by step
- 1
Choose a category
Length, weight, volume or temperature.
- 2
Pick your units
Select the unit you are converting from and the one you want.
- 3
Enter a value
The converted result updates as you type.
- 4
Swap if needed
Use the swap control to reverse the conversion without re-selecting units.
Frequently asked questions
How do I convert Celsius to Fahrenheit?
Multiply by 9/5 and add 32. Unlike other conversions this is not a simple ratio, because the two scales start at different zero points.
How many grams are in an ounce?
One ounce is 28.35 grams, and one pound is 453.6 grams.
How many kilometres are in a mile?
One mile is 1.609 kilometres, and one kilometre is 0.621 miles.
Why do US and UK cups and pints differ?
They are genuinely different measures — a US pint is 473 ml while a UK pint is 568 ml. Check which system a recipe uses before converting, or the result will be noticeably off.
Is anything I enter uploaded?
No. All conversions are calculated in your browser.