Unit Converter
A unit converter that answers the question you did not ask yet: type one value and see it in every unit of that category at once, each row copyable, with proper affine handling for temperature.
How to use Unit Converter
- Choose a category — length, mass, temperature, volume, area, speed, time, data, pressure, energy, power, angle or fuel economy.
- Type a value and pick the unit it is in. Every other unit in the category updates live.
- Use the search box to filter a long unit list down to the one you want.
- Click any row to copy that converted value, or download the whole table as CSV.
About Unit Converter
Most unit converters ask you to pick a “from” unit and a “to” unit, then give you a single number. That is one answer to a question you had to phrase perfectly. This converter inverts the idea: pick a category, type a value, and it renders the value in every unit in that category simultaneously. You get centimetres, inches, feet, metres and yards in one glance — useful when you are not converting so much as trying to develop a feel for a quantity, or when you need two different target units for the same figure.
Correctness lives in the details. Length carries exact SI-derived factors down to the ångström and out to the parsec. Mass distinguishes the troy ounce from the avoirdupois ounce, and the short ton from the long ton. Volume keeps US and imperial fluid measures separate — an imperial pint is 568 ml, a US pint is 473 ml, and recipes ruined by that difference are a genuine phenomenon. Temperature uses affine conversion with offsets, so Celsius, Fahrenheit, Kelvin, Rankine and Réaumur all agree at every point rather than only at zero.
Fuel economy gets special treatment because it is the one category where the relationship is inverse: litres per 100 km goes down as miles per gallon goes up, so no multiplication factor can convert between them. The tool applies the reciprocal relationship directly, and keeps US and imperial gallons distinct, which is why a car rated 40 mpg in the UK is only 33 mpg in the US with no change to the car at all.
Frequently asked questions
How accurate are these conversions?
Conversion factors are the exact internationally defined values — an inch is exactly 25.4 mm, a pound is exactly 0.45359237 kg, a US gallon is exactly 3.785411784 L. Arithmetic is done in IEEE-754 double precision and only rounded for display, so round-tripping a value returns the number you started with.
Why is temperature converted differently from other units?
Temperature scales have offsets as well as different step sizes, so conversion is affine rather than a simple multiplication: °C = (°F − 32) × 5/9, not °F × some factor. Treating temperature as a scale factor is the most common conversion bug on the web, and it is why 0°C would wrongly come out as 0°F.
What is the difference between a megabyte and a mebibyte?
A megabyte (MB) is 1,000,000 bytes — the decimal definition used by drive manufacturers and networks. A mebibyte (MiB) is 1,048,576 bytes, the binary definition your operating system usually reports. Both appear in the digital storage category so you can see the gap that makes a “1 TB” drive show as 931 GB.
Does it handle very large or very small numbers?
Yes. Values outside a readable range switch to scientific notation with a proper exponent rather than a wall of zeros, and significant figures are kept consistent across the table.
Is anything uploaded?
No. The whole conversion table is computed in your browser, so it works offline and nothing you type is transmitted.
Related tools
- BMI Calculator — BMI, BMR, TDEE & calorie targets
- Percentage Calculator — Every percentage question, worked out
- Loan Calculator — Payment, interest & full amortisation
- Age Calculator — Exact age, to the day and minute
- Compound Interest Calculator — Growth, contributions & real returns
- Date Calculator — Days between dates & business days