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Length Converter – Metres, Feet, Inches, Miles and Yards

Use this length converter to switch between metric and imperial distances, from millimetres to nautical miles.

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Runs in your browser – your data never leaves your device Also available via our free API

Common conversions

From unit Value To unit Result
Inches (in) 1 Centimetres (cm) 2.54
Feet (ft) 1 Metres (m) 0.3048
Yards (yd) 1 Metres (m) 0.9144
Miles (mi) 1 Kilometres (km) 1.6093
Nautical miles (nmi) 1 Kilometres (km) 1.852
Metres (m) 1 Feet (ft) 3.2808
Kilometres (km) 1 Miles (mi) 0.6214

How to use the Length Converter

  1. 1 Enter the length you want to convert.
  2. 2 Choose the unit you are converting from, such as feet or metres.
  3. 3 Choose the target unit; the result updates as you type. Use ⇄ to reverse the conversion.

How length conversion works

Every length is first converted to metres and then to the target unit. The imperial units are defined exactly in metric terms since the 1959 international yard and pound agreement: one inch is exactly 2.54 cm, one foot is 0.3048 m, one yard is 0.9144 m and one mile is 1,609.344 m. Because these factors are exact, the converter does not introduce rounding beyond the 12 significant digits it displays.

Metric and imperial length units

  • Millimetres, centimetres and decimetres – small measurements such as screws, paper and body height.
  • Metres and kilometres – rooms, buildings, running and road distances.
  • Inches, feet and yards – screens, timber, sports fields and US building plans.
  • Miles – road distances in the United States and the United Kingdom.
  • Nautical miles – sea and air navigation; one nautical mile is exactly 1,852 m.

Quick mental conversions

For a rough answer without a calculator, a metre is a little more than 3 feet 3 inches, a kilometre is about 0.62 miles and a mile is about 1.6 km. To turn centimetres into inches, divide by 2.5; to turn feet into metres, multiply by 0.3. Use the exact result above when accuracy matters, such as for construction, sewing or technical drawings.

Feet and inches together

Heights are often written as feet and inches, for example 5 ft 10 in. Convert the feet and inches separately and add them: 5 ft is 152.4 cm and 10 in is 25.4 cm, so 5 ft 10 in is 177.8 cm.

Screen sizes and other inch measurements

TVs, monitors, phones and bicycle wheels are sold by the inch almost everywhere. A 27-inch monitor has a diagonal of 68.6 cm and a 65-inch TV about 165 cm. Remember that the diagonal is not the width: a 16:9 screen is about 87% as wide as its diagonal.

Sources

Conversion factors follow the SI definitions in the BIPM SI Brochure and the exact factors for US customary and imperial units in NIST Special Publication 811.

Frequently asked questions

How many feet are in a metre?

One metre is 3.28084 feet, or about 3 feet 3.37 inches.

How many centimetres are in an inch?

Exactly 2.54 centimetres. This is the international definition of the inch.

How many kilometres are in a mile?

One mile is exactly 1.609344 kilometres. One kilometre is about 0.621 miles.

What is the difference between a mile and a nautical mile?

A statute mile is 1,609.344 m, while a nautical mile is 1,852 m. Nautical miles are used at sea and in aviation.

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