SSmartNtools

Unit Converter

Convert length, weight, volume, area, speed and digital data between dozens of units quickly and for free.

Result
1,000 Meter (m)
1 Kilometer (km) = 1,000 Meter (m)

How unit conversion works

Each category has a reference unit (the base unit). Every other unit is defined as a multiple of that base, which lets us convert any value in a single step: the value is turned into the base unit and then into the target unit.

The factors follow the international (SI) standards and the usual imperial and US definitions. For digital data we use binary multiples (1 KB = 1024 bytes).

Frequently asked questions

Which unit categories can I convert?

Length, weight/mass, volume, area, speed and digital data, each with several metric and imperial units.

Are the conversions accurate?

Yes. We use the official conversion factors; the result is shown with up to 6 decimal places to keep precision.

Are gallons US or imperial?

We use US gallons and fluid ounces. 1 US gallon equals about 3.785 liters.

Why is 1 KB equal to 1024 bytes and not 1000?

For digital data we use the traditional binary convention, where each multiple is a power of 2 (1024).

How many centimetres are in an inch?

Exactly 2.54 cm. That value is a definition, not a measurement, so conversions between inches and centimetres are exact rather than approximate.

How do I convert kilometres to miles?

Multiply kilometres by 0.621371, or divide by 1.609344. So 10 km is 6.21 miles and a marathon at 42.195 km is 26.22 miles.

What is the difference between a US and an imperial gallon?

A US gallon is 3.785 litres and an imperial (UK) gallon is 4.546 litres — about 20% larger. Fuel-economy figures are not comparable between the two without converting.

Are the conversion factors exact?

The metric-imperial factors used here are the internationally defined values, so results are limited only by the rounding you choose to display.

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