Formula
value in target unit = value × (base units per source unit) ÷ (base units per target unit)
- Each category has one base unit: metre, kilogram, square metre, cubic metre, metre per second, second or byte.
- Temperature and fuel economy use their own formulas.
Convert to the category's base unit, then to the unit you want.
Worked examples
2 hours in minutes
- Category
- Time
- Value
- 2
- From
- Hour (h)
- To
- Minute (min)
Hour to Minute
120 min
In words: 2 h = 120 min
1 GiB in MB
- Category
- Digital storage
- Value
- 1
- From
- Gibibyte (GiB)
- To
- Megabyte (MB)
Gibibyte to Megabyte
1,073.741824 MB
In words: 1 GiB = 1,073.741824 MB
How it works
Every unit in a category is defined relative to one base unit, so any pair converts through it. An hour is 3,600 seconds and a day is 86,400, which is why 1 hour is 1/24 of a day exactly. Months and years are not fixed lengths, so the time category uses Gregorian averages (30.436875 and 365.2425 days) and labels them “average”.
For digital storage there are two conventions. KB, MB, GB and TB follow the SI prefixes (powers of 1,000), which is what drive makers and networks use. KiB, MiB, GiB and TiB are powers of 1,024, which is how most operating systems count memory. That is why a “500 GB” drive shows up as about 465 GiB.
Dedicated pages give more detail for each category: Length Converter, Weight Converter, Temperature Converter, Area Converter, Volume Converter, Speed Converter and Fuel Economy Converter.
Assumptions and limits
- Switching category resets the two unit selections.
- Results are shown to up to 10 significant digits.