A unit converter that covers the measurements you actually reach for: length, weight, volume, temperature, area, speed and digital storage. Conversions update as you type, in both directions, using exact factors rather than rounded approximations — so an inch is 25.4 millimetres, not 25.4-ish.
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Unit ConverterLive
This tool is built for a wider screen — scroll sideways inside the frame, or turn your device.
How to use it
Four steps to a result
Choose a category
Pick length, weight, volume, temperature, area, speed or data. Each category loads only the units that belong to it.
Enter a value
Type into either field. Conversion runs in both directions, so you can work backwards from the target figure just as easily.
Switch units freely
Change the source or target unit at any time and the result updates immediately, keeping the value you already typed.
Copy the result
Copy the converted figure at the precision you need — useful when the answer is going into a spec, an invoice or a CSS declaration.
Questions
Frequently asked questions
Length, mass and weight, volume, temperature, area, speed and digital storage, each with the metric and imperial units in common use — plus the awkward ones such as US versus imperial fluid ounces, which differ by about four percent and quietly ruin recipes.
They use exact definitions where one exists: one inch is exactly 25.4 millimetres, one pound is exactly 0.45359237 kilograms. Results are computed at full floating-point precision and only rounded for display, so chained conversions do not accumulate error.
Choose the temperature category and enter your value. Temperature is an offset scale rather than a simple ratio, so the conversion applies the correct formula rather than a multiplier — which is why 0°C is 32°F and not 0°F.
Yes, and it distinguishes the two systems that get conflated: decimal units where a kilobyte is 1,000 bytes, used by drive manufacturers, and binary units where a kibibyte is 1,024 bytes, used by operating systems. That difference is why a 1 TB drive shows up as roughly 931 GB.
Yes. All conversion factors are built into the page, so once it has loaded there is no network request and it works with the connection off.
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