Convert any unit. Instantly.
Free online unit converter for length, weight, temperature, area, volume, speed, time, data sizes, pressure, energy and fuel economy. Instant results, reference tables and conversion history — no signup, works offline.
Length
Convert between metric and imperial units of length.
Everything you need to convert with confidence.
11 Unit Categories
Length, weight, temperature, area, volume, speed, time, digital data, pressure, energy and fuel economy — all in one place.
Instant Live Conversion
Type a value and see the result update immediately. No button to press, no page to reload.
Metric & Imperial
Full support for both metric and imperial units, plus common specialised units like nautical miles and knots.
Temperature Formulas
Celsius, Fahrenheit and Kelvin use the correct linear formulas — no approximated offsets, no rounding surprises.
Decimal & Binary Data
Convert between bits, bytes, KB, MB, GB, TB and their binary equivalents KiB, MiB, GiB, TiB — no more 500 GB confusion.
Reference Tables
Every category includes a quick reference table of the most common conversions so you can check common values at a glance.
Conversion History
Your recent conversions are stored locally so you can click any of them to reload the exact same conversion.
Copy Results
Copy just the result or the full conversion including both units and the source value — ready to paste anywhere.
100% Private & Offline
Every conversion happens in your browser. Nothing is uploaded, and after the page loads you can keep using it with no internet.
Convert a unit in 3 simple steps.
Pick a category
Choose Length, Weight, Temperature, Data, Area, Volume, Speed, Time, Pressure, Energy or Fuel Economy from the tabs at the top. The converter switches to that category instantly.
Enter your value
Type any number in the "From" field and choose your source and target units. The result updates live as you type — no need to press a convert button.
Copy or check the reference
Click "Copy result" for just the number, or check the quick-conversion cards and reference table on the right for common values in the same category.
Frequently Asked Questions.
The converter supports eleven categories: length, weight and mass, temperature, area, volume, speed, time, digital data sizes, pressure, energy, and fuel economy. Each category includes both metric and imperial units along with common specialised units.
Select the Length category, choose Centimeters as the source unit and Inches as the target unit, then enter the number of centimeters. The result appears instantly. One inch equals exactly 2.54 centimeters.
Yes. It is 100% free with no signup, no ads in the tool, and no hidden charges. Use it as often as you like, and your conversion history stays only in your own browser.
Yes. Once the page has loaded, all conversions are computed locally in your browser. You can disconnect from the internet and keep converting.
Conversions use the internationally defined exact conversion factors wherever they exist — for example, 1 inch = 2.54 cm exactly, 1 pound = 453.59237 grams exactly — and high-precision factors for the rest. Results are displayed with up to eight significant digits.
Select the Temperature category and choose Celsius as the source and Fahrenheit as the target. The formula is F = C × 9/5 + 32. The converter applies this automatically, so you can simply type the Celsius value and read the Fahrenheit result.
MB is the decimal megabyte (1,000,000 bytes) while MiB is the binary mebibyte (1,048,576 bytes). Storage manufacturers usually quote decimal sizes while many operating systems report binary sizes, which is why a 500 GB drive may show as roughly 465 GiB. The converter includes both so you can see the difference clearly.