CalcMate

Length Converter

Convert lengths and distances between millimetres, centimetres, metres, kilometres, inches, feet, yards, and miles instantly.

How to use the length converter

Enter a value and choose the unit it is in. The converter instantly shows the equivalent in every other supported unit — millimetres, centimetres, metres, kilometres, inches, feet, yards, and miles — so you never have to convert one pair at a time. Everything runs in your browser.

Metric and imperial in one place

Length is one of the most common things people need to convert, whether reading a recipe, following an overseas measurement, sizing furniture, or planning a run. Because this tool shows all units together, it bridges metric and imperial in a single glance rather than forcing you to pick a specific conversion direction. Switch the source unit and the whole list updates.

Exact by design

All the conversions here rest on exact, internationally agreed definitions: an inch is exactly 2.54 centimetres, a foot exactly 0.3048 metres, and a mile exactly 1,609.344 metres. That means the results are precise, with any rounding appearing only in the displayed figure. For very large or very small values the converter switches to scientific notation so the answer stays readable. Nothing you enter is stored.

Popular length conversions

CM to Inches1 cm = 0.3937008 inInches to CM1 in = 2.54 cmMeters to Feet1 m = 3.28084 ftFeet to Meters1 ft = 0.3048 mKM to Miles1 km = 0.6213712 miMiles to KM1 mi = 1.609344 kmMM to Inches1 mm = 0.03937008 inInches to MM1 in = 25.4 mmYards to Meters1 yd = 0.9144 mCM to Feet1 cm = 0.0328084 ft

Frequently Asked Questions

How do I convert centimetres to inches?

Divide the number of centimetres by 2.54, since one inch is exactly 2.54 cm. So 100 cm ÷ 2.54 = 39.37 inches. To go the other way, multiply inches by 2.54 to get centimetres.

How many feet are in a metre?

One metre equals about 3.281 feet, because a foot is defined as exactly 0.3048 metres. To convert metres to feet, divide by 0.3048 or multiply by 3.281; to convert feet to metres, multiply by 0.3048.

How do I convert miles to kilometres?

Multiply miles by 1.609344, since one mile is exactly 1.609344 km. A 5-mile run is about 8.05 km. To convert kilometres to miles, divide by 1.609344 or multiply by roughly 0.621.

Are these conversions exact?

The relationships between imperial and metric units are defined exactly — an inch is exactly 2.54 cm, a mile exactly 1609.344 m — so the conversions are precise. Any rounding you see is only in how the result is displayed, not in the underlying calculation.

What is the difference between metric and imperial length units?

Metric units (mm, cm, m, km) are based on powers of ten, so converting between them just moves the decimal point. Imperial units (inches, feet, yards, miles) use different multipliers — 12 inches to a foot, 3 feet to a yard, 1,760 yards to a mile — which is why a converter is handy.

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