Unit Converter
Convert between all common units: length, weight, temperature, volume, area, speed, and more. Fast and accurate.
About this calculator
One converter for the nine categories people use most: length, weight, temperature, volume, area, speed, energy, pressure and data storage. Choose a category, pick the From and To units, type a value and the other side fills in at once.
The swap button reverses the units so you can check a result in both directions. Factors are exact, for example 1 inch = 2.54 cm, 1 pound = 0.45359237 kg and 1 kWh = 3.6 MJ, and temperature uses the proper offset formulas.
How to use it
- Choose a Category.
- Pick the From and To units and type the From value.
- Read the answer in the To box. Press ⇄ to swap.
How conversion works
Every conversion goes through a base unit: the tool converts your value to the base, then from the base to each target. That keeps results consistent in both directions, so converting A to B and back returns the number you started with.
For length, weight, area, volume, speed, energy, pressure and data storage, result = value × from-factor ÷ to-factor. Temperature adds offsets: °F = °C × 9/5 + 32 and K = °C + 273.15.
Worked example
One example in each category
| Length | 10 km = 6.2137 miles |
| Weight | 70 kg = 154.32 lb |
| Temperature | 37 °C = 98.6 °F |
| Volume | 5 L = 1.3209 US gallons |
| Area | 1 acre = 4,046.86 m² |
| Speed | 100 km/h = 62.14 mph |
| Energy | 1 kWh = 860.4 kcal |
| Pressure | 32 psi = 2.206 bar |
| Data | 1 GB = 1,024 MB |
Tips and common mistakes
- Check the pair of units before reading the answer, especially US vs UK gallons.
- For temperature use the proper formula, not a ratio.
- Convert in two steps if a pair is not offered: go through a common unit.
- Keep extra decimals for chained work and round at the end.
- Use the category-specific converters on this site for more units, such as bigha and guntha for land.
Frequently asked questions
What conversions does this tool support?
Length, weight, temperature, volume, area, speed, energy, pressure and data storage.
Are the factors exact?
Yes, they use the international definitions.
Why does my result differ from another site?
Rounding, or a different definition such as US vs UK gallon.
Can I convert between categories, such as length to weight?
No, only like with like.
How do I convert Celsius to Fahrenheit?
Multiply by 9/5 and add 32.
Does it work offline?
Once the page has loaded, the maths runs in your browser.