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Unit Converter

Convert length, weight, temperature, time, data, pressure, energy, and more

3.28083989501 ft
1 m = 3.28083989501 ft
1 m = 3.28083989501 ft

About Unit Converter

Unit Converter covers 12 categories: Length, Weight, Temperature, Fuel economy, Speed, Area, Volume, Time, Data, Pressure, Energy, and Power. Every factor is an exact definition, such as 1 inch = 25.4 mm, 1 lb = 0.45359237 kg, or 1 calorie = 4.184 J, so results are not built on rounded constants. The answer updates as you type and keeps up to 12 significant digits. Temperature and fuel economy use formulas instead of factors, because their scales start at different zeros or run in opposite directions. Money is not covered here: the Currency Converter does that with daily rates.

Example

Six conversions and the result the page shows for each (the page's own factors and display code, run in Node on October 6, 2026).

Category, value, and units

Length: 1 mile → km
Length: 1 km → inch
Temperature: 100 F → C
Fuel economy: 8 L/100 km → mpg (US)
Data: 1 GiB → MB
Pressure: 1 psi → kPa

Result

1.609344 km
39370.0787402 inch
37.7777777778 C
29.4018229167 mpg (US)
1073.741824 MB
6.89475729317 kPa

How to convert units

  1. 1Click a category button such as "Length", "Fuel economy", or "Data"; "From" and "To" switch to its first two units.
  2. 2Type the number in "Value": decimals with a comma or a period, negative values, and forms like 6.02e23 work.
  3. 3Pick the units in "From" and "To".
  4. 4Read the result; for every category except temperature and fuel economy, the line below it gives the factor for one unit.

Formats and limits

Categories
Length, Weight, Temperature, Fuel economy, Speed, Area, Volume, Time, Data, Pressure, Energy, Power
Some of the units
nm to nautical miles; stone, carat, US and UK tons; Celsius, Fahrenheit, Kelvin, Rankine; L/100 km, km/L, mpg US and UK; bits, kB to PB, and KiB to TiB; Pa to MPa, mbar, bar, atm, psi, mmHg, inHg, torr; J to MJ, Wh, kWh, cal, kcal, BTU, eV, ft·lbf; W, kW, MW, hp, metric hp, BTU/h, kcal/h
Precision
Up to 12 significant digits; scientific notation below 0.000001 and from 1e15 up
Typing
A comma or a period marks the decimals (12,5 = 12.5); 1,000 or 1.000 could be a thousand or one, so the page shows no result and asks for 1000 or 1; thousands separators are not read
Checks
A warning below absolute zero; fuel economy must be above 0

Where your values are processed

Each result is your value multiplied by fixed factors written in the page, or put through the temperature and fuel economy formulas, all in your browser; the values you type are not sent anywhere. Should the converter crash, our error watch sends the cleaned error message with the tool's name and your browser's name and major version, never the value or the units you chose.

Frequently asked questions

Is a kilobyte 1000 or 1024 bytes here?

1000. The page follows the SI prefixes: kB, MB, GB, TB, and PB are powers of 1000, while KiB, MiB, GiB, and TiB are powers of 1024, and bits are listed separately. So 1 GiB converts to 1073.741824 MB.

Are US and UK gallons different?

Yes. A US gallon is 3.785411784 liters and a UK gallon 4.54609 liters. Volume lists both, along with US and UK pints and fluid ounces, and Fuel economy offers mpg (US) and mpg (UK), which differ for the same reason.

How precise are the results?

12 significant digits at most, from exact definitions in NIST SP 811: 1 psi is 6894.757… Pa and 1 BTU is 1055.05585262 J. A month is one twelfth of a Gregorian year of 365.2425 days, and calories are thermochemical (4.184 J).

Why is there no factor line for temperature?

No single factor exists. Celsius, Fahrenheit, Kelvin, and Rankine start at different zero points, and L/100 km is the inverse of km/L, so the page converts them with formulas and shows only the result.

Tips and tricks

  • ✓Paste figures written with a decimal comma, such as 12,5 from a European spreadsheet: the page reads them as 12.5.

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