Unit Converter

Convert length, weight, area, temperature, speed & data.

A unit converter is a tool that changes a measurement from one unit into another — feet to metres, kilograms to pounds, Celsius to Fahrenheit. This all-in-one converter covers length, weight (mass), area, temperature, speed and digital data storage, switching between metric and imperial with instant results and a full conversion table. Runs fully in your browser — nothing is uploaded.

How to use Unit Converter

  1. Pick a category

    Choose a measurement category in this free online unit converter — length, weight, area, temperature, speed or digital data storage — from the tab bar.

  2. Enter a value

    Type the number you want to convert into the From field and the result updates instantly, with invalid input flagged so your conversion stays accurate.

  3. Select the units

    Pick your from and to units, such as cm to inches, kg to lbs or Celsius to Fahrenheit, using the searchable metric and imperial unit dropdowns.

  4. Swap directions

    Click the swap button to instantly reverse the from and to units and carry the converted value across, flipping the conversion the other way round.

  5. Scan the full table

    Read the whole-category conversion table to see your value expressed in every unit at once, making it easy to compare measurements side by side.

  6. Copy any result

    Tap the copy icon to grab the converted answer or any row from the table, ready to paste anywhere — everything runs privately in your browser.

Frequently asked questions

How do I convert between units like cm to inches or kg to lbs?

Choose the category (e.g. Length or Weight), enter your value, then pick the “from” and “to” units — say centimetres and inches, or kilograms and pounds. The converted result appears instantly, and the table below shows the same value in every other unit in that category.

How do I convert Celsius to Fahrenheit?

Open the Temperature category, type the temperature in the Celsius field and read the Fahrenheit value, or swap the units to go the other way. It uses the exact formula °F = °C × 9/5 + 32 (and °C = (°F − 32) × 5/9), and also supports Kelvin.

What is the difference between a kilobyte (KB) and a kibibyte (KiB)?

A kilobyte is the decimal unit: 1 KB = 1,000 bytes. A kibibyte is the binary unit: 1 KiB = 1,024 bytes. Storage makers usually advertise in decimal (KB, MB, GB) while operating systems often report in binary (KiB, MiB, GiB) — which is why a “1 TB” drive shows as ~931 GiB. This converter supports both families.

Why isn't weight the same as mass?

Strictly, mass (kilograms, pounds) is the amount of matter, while weight is the force gravity exerts on it. In everyday use the terms are interchangeable, and like every common converter this tool treats kg, lb, oz and so on as units of mass.

How accurate are the conversions?

Linear units (length, weight, area, speed, data) use exact internationally-defined factors, so results are precise; they're rounded to about 12 significant digits for display, with very large or very small numbers shown in scientific notation. Temperature uses the exact offset formulas.

Which is the short ton vs the metric tonne?

The metric tonne (t) is 1,000 kg. The US (short) ton is 2,000 pounds ≈ 907.18 kg. This tool uses the metric tonne and the US short ton; the UK long ton (2,240 lb) isn't listed to keep the picker clean.

Is my data sent anywhere?

No. All conversions run entirely in your browser with a dependency-free maths library. Nothing you type is uploaded, logged or stored.

How do I convert meters to feet or feet to meters?

Open the Length category, type your value in the metres field to read feet (1 m = 3.28084 ft), or enter feet to get metres the other way. The full table also shows the same length in centimetres, inches, kilometres and miles at once.

How do I convert miles to kilometres?

In the Length category, enter the value in miles to see kilometres instantly — the tool uses the exact factor 1 mile = 1.609344 km. Swap the units to convert kilometres back to miles.

Is the unit converter free to use?

Yes — it's completely free with no sign-up and no limits, and it runs entirely in your browser. Convert as many values across length, weight, temperature, area, speed and data as you like on any device.

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