Unit Converter
Convert length, weight, temperature, area, volume, speed, data size and time units. See every value in one table.
How it works
- Pick a category: length, weight, data size and others.
- Type the value and choose the source and target units.
- Read the result and see every unit in the table below.
Why this tool
- Eight categories: length, weight, temperature, area, volume, speed, data, time.
- Data size holds both 1000 based (KB) and 1024 based (KiB) units.
- Every unit of the category appears in one table.
- Swap the source and the target with one button.
- Download the result as txt. The math runs in your browser.
Data size units are confusing because of two counting systems. Computers work in binary, so 1024 is a natural step. In the metric system the prefix kilo means 1000. For years the two were mixed: a kilobyte meant 1000 bytes in one place and 1024 bytes in another.
In 1998 the IEC defined binary prefixes. KiB is 1024 bytes. MiB is 1048576 bytes. GiB is 1073741824 bytes. KB, MB and GB stay on the 1000 base. This tool lists both sets on separate rows.
Who uses which one? Drive and USB stick makers use the 1000 base. A box that says 1 TB means 1000000000000 bytes. Internet speeds also use the 1000 base and count bits, so 100 Mbps is 12.5 megabytes per second. Windows divides by 1024 but prints the label "GB". macOS and iOS have used the 1000 base since 2009.
That is why a 1 TB drive shows as 931 GB in Windows. Nothing is lost. There are two different divisions. You can repeat the math here: enter 1 TB and convert to TiB. The result is 0.909.
In the other categories the factors come from international definitions. An inch is exactly 0.0254 meter. A pound is exactly 0.45359237 kilogram. A nautical mile is exactly 1852 meters. Temperature uses a formula, not a factor, because the scales have different zero points.
The math runs in your browser. There is no network request.
Frequently asked questions
What is the difference between KB and KiB?
KB is 1000 bytes and KiB is 1024 bytes. Drive makers and network speeds use the 1000 base. Windows uses the 1024 base but prints the label "KB". That is the source of the confusion.
Why is my drive smaller than the box says?
A 1 TB drive holds 1000000000000 bytes. Windows divides by the 1024 base and shows 931 GB. Nothing is lost. There are two different counts.
Why is temperature not a simple factor?
The temperature scales have different zero points. From Celsius to Fahrenheit you first multiply by 1.8 and then add 32.
What is a dunam?
In this tool one dunam is 1000 square meters. The old Ottoman dunam was about 919 square meters. Land records now use the 1000 square meter value.
Which gallon do you use?
There are two. The US gallon is 3.785 liters and the UK gallon is 4.546 liters. Both appear as separate units.
How precise are the results?
Values show up to eight significant digits. The factors come from international definitions. An inch is exactly 0.0254 meter and a pound is exactly 0.45359237 kilogram.