Unit converter.
Convert a value between units of length, mass, temperature, area, volume, speed, data and time, and read it in every unit of its kind. Exact factors, in your browser.
Unit converter.
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3 steps, no account. It runs in your browser and nothing is uploaded.
Pick a category
Length, mass, temperature, area, volume, speed, data or time.
Type a value and choose two units
The result updates as you type, with the rate for one unit under it.
Read it in every unit
The value in every unit of the category, listed under the result.
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Questions and answers
Before you trust the result: what to know about the format, the limits, your data and the tools next to it.
Length (millimetre to nautical mile), mass (milligram to US ton), temperature (Celsius, Fahrenheit, Kelvin), area (square millimetre to square mile, acre and hectare), volume (millilitre to cubic foot, US and UK gallons, cups and spoons), speed (m/s, km/h, mph, knots, Mach), data (bits and bytes, decimal and binary prefixes) and time (millisecond to year).
Through a base unit: a value is multiplied by its unit's factor to the base (the metre, the kilogram, the litre), then divided by the target's. Temperature is the exception, with an offset applied first, so 0 °C is 32 °F and 273.15 K.
The international definitions: an inch is exactly 25.4 mm, a pound exactly 0.45359237 kg, a US gallon 3.785411784 litres. Results are shown to ten significant digits with float noise removed.
A kilobyte (kB) is 1000 bytes and a kibibyte (KiB) is 1024, which is why a 500 GB drive shows as 465 GiB. Both prefixes are in the data category so the two can be compared.
Pick the category, type a value and choose the two units; the result updates as you type, and the line under it gives the rate for one unit. Swap exchanges the two.
Under the result, the value is listed in every unit of the category at once, so you can read 1 mile in kilometres, yards, feet and inches in one glance.
No. The factors are part of the page and the arithmetic runs in your browser; nothing is sent anywhere.
No. The Unit converter is free and opens without a sign-in, an account or an install.
The Unit converter keeps nothing on a server; only the invoice generator saves its draft, in this browser's localStorage on your device. Nothing else is saved, and nothing is sent to shadcn.io.
8 categories: length, mass, temperature, area, volume, speed, data, time.
Under the result, the value is listed in every unit of the category at once, so you can read a mile in kilometres, yards, feet and inches together.
Press the Swap button: it exchanges the two units.
Closest to the Unit converter: Calculator, Currency converter, Number base converter, Time zone converter. Each opens on its own page, free and in the browser.
The Unit converter is one of 20 in its group. The group's page, /tools/math, lists them all.
The tool is free. Its interface is built from shadcn.io's own components (Button, Input, Slider and the rest of the registry under /ui), which come in React, Vue, Svelte and Solid. Pro adds the blocks and templates for the product around it.
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