Unit Converter: how to use it
Convert length, weight, temperature, volume, speed and digital storage units, with the conversion factors explained.
Recipes in cups, a car's speed in miles per hour, a parcel weighed in pounds, a file measured in megabytes: everyday life mixes unit systems, and one wrong conversion can ruin a result. The Unit Converter handles six common categories and shows the converted value immediately.
Pick a category, choose the two units and type a value. The Swap units button reverses the direction in one click.
How to use the Unit Converter
- Choose a Category: Length, Weight / mass, Temperature, Volume, Speed or Digital storage (decimal).
- Enter the Value you want to convert.
- Pick the From and To units.
- Press Convert to see the answer, or Swap units to reverse the conversion.
Tips for better results
- Temperature is not a simple multiplication. Celsius to Fahrenheit is C x 9/5 + 32, so 100 degrees Celsius is 212 degrees Fahrenheit.
- One inch is exactly 2.54 centimetres and one mile is about 1.609 kilometres. These are the factors behind most length conversions.
- Cups and gallons differ between the US and the UK. Check which system your recipe or product uses.
- Speed: 100 km/h is about 62.1 mph, and 1 m/s equals 3.6 km/h.
Digital storage is decimal here
Storage makers sell drives using decimal units: 1 kilobyte is 1,000 bytes, 1 megabyte is 1,000 kilobytes and so on. Operating systems often display binary units, where 1,024 is used, which is why a 500 GB drive appears smaller in your computer. This converter uses the decimal definition and labels it clearly.
Frequently asked questions
How precise are the results?
They are accurate to many decimal places and rounded for display.
Can I convert between categories, such as kilometres to kilograms?
No. Units must measure the same kind of thing.
Does it work offline?
Once the page has loaded, the calculation runs in your browser and needs no connection.
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