Unit Converter
Converts length, weight, area, volume, temperature, speed, pressure and data units, including Korean units.
One value in, every equivalent out: length, weight, area, volume, temperature, speed, pressure and data. The Korean units are here as first-class entries rather than as an afterthought, so 평 and 돈 and 근 convert without a second lookup.
Read the way this page’s language writes numbers, spaces ignored. Anything that does not fit is refused rather than guessed at.
Converted
- mm1,000millimetre
- cm100centimetre
- m1metre
- km0.001kilometre
- in39.3700787402inch
- ft3.28083989501foot
- yd1.09361329834yard
- mi0.000621371192237mile
- nmi0.000539956803456nautical mile
- 자3.3ja (尺)
- 치33chi (寸)
- 리0.0025462962963ri (里)1296 자, about 392.7 m. The Japanese 里 is ten times longer and the Chinese 市里 is 500 m: one character, three distances.
Factors are exact where the unit is defined exactly — an inch is 25.4 mm, a 평 is 400/121 ㎡ — so the results do not drift the way a chain of decimal constants does.
How to use it
Pick the category
Length, weight, area and the rest. This is what decides which units are offered — a converter that let you turn kilograms into metres would be a worse tool, not a more flexible one.
Type the value and choose what it is in
The number is read the way this page’s language writes one: here the comma groups the thousands and the dot marks the decimal, so a 1,234.56 copied out of a spreadsheet pastes straight in, and 1,5 is refused rather than read as fifteen. On the pages whose language marks the decimal with a comma — Spanish, Portuguese, German, French, Italian — it is the other way round. Spaces are ignored either way. The field takes one value, so a comma that is not grouping is an error here rather than the start of a second number. Everything else on the page recalculates as you type.
Read the whole column, not one answer
Every unit in the category is shown at once, which is usually faster than deciding in advance which one you wanted. Copy all takes the lot to the clipboard.
Common questions
How big is a 평, exactly?
Exactly 400/121 square metres, about 3.3058. That fraction is what is used here, not the rounded 3.3058, so converting 100 평 to square metres and back gives 100 rather than 99.9998.
Why are some units marked as customary?
Because they have no single legal definition. A 근 is 600 g for meat and 375 g for vegetables and herbs, and no standards body settles it. The mark tells you the number is a convention, not a definition.
Can I convert a temperature below absolute zero?
The arithmetic runs and the page says so. Temperature conversion is an affine formula that has no opinion about physics, so −300 °C converts happily; the note is there because the number is meaningless, not because the conversion is wrong.
Is a US gallon the same as an imperial one?
No, and they are separate entries here. A US liquid gallon is 3.785 L and an imperial gallon is 4.546 L — twenty per cent apart, which is enough to matter in any recipe or fuel figure.
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