Length Converter

Exact definitions. Since the international yard and pound agreement of 1959, imperial lengths are defined in metres:

• 1 inch = 2.54 cm exactly.
• 1 foot = 12 inches = 0.3048 m.
• 1 yard = 3 feet = 0.9144 m.
• 1 mile = 1,760 yards = 1,609.344 m.
• 1 nautical mile = 1,852 m, used at sea and in aviation.

The converter changes your value to metres, then to the target unit, so every pair uses the exact factors and there is no rounding chain.

Feet and inches. Heights and room sizes are usually given as feet and inches. Type 5'10", 5 ft 10 in or just 5' and the tool reads it as inches, ignoring the From setting: 5'10" is 70 inches, or 177.8 cm. Every result is also shown in feet and inches, so 100 metres is 328 feet 1.01 inches.

Quick reference.

• 1 m ≈ 3.281 ft ≈ 39.37 in.
• 1 km ≈ 0.621 miles; 1 mile ≈ 1.609 km.
• 1 ft = 30.48 cm; 6 ft ≈ 1.83 m.
• 10 km ≈ 6.2 miles; a marathon is 42.195 km, about 26.2 miles.
• 100 yards (an American football field without end zones) is 91.44 m.

Mental shortcuts. For kilometres to miles, multiply by 0.6 (more precisely, 5 km is 3.1 miles). For metres to feet, multiply by 3 and add 10%. For inches to centimetres, multiply by 2.5. These are close enough for everyday estimates but not for building or engineering work.

Survey feet and history. Before 2023, the US also had a "survey foot" of 1200/3937 m, about 2 parts per million longer than the international foot, used for land surveying. It was officially retired at the end of 2022, but older property records and maps may still use it; over a mile, the difference is about 3 mm. Older units such as the gaz, still used informally in Pakistan and India for fabric and land (one gaz is commonly taken as a yard), vary by region and are not included.

Choosing units.

• Use metres and centimetres for building plans in most of the world; architects often work in millimetres.
• Use feet and inches for US construction and for heights in the US and UK.
• Road distances are in miles in the US and UK and kilometres almost everywhere else.
• Screen sizes are given in inches diagonally.

Precision. Results are shown to six decimal places, or eight for very small values, with thousands separators. Round to the precision you can actually measure: a tape measure reads to about a millimetre or 1/16 inch.

Plural units. Unit names follow the number, so 1 mile but 1.6 kilometres, and 1 foot but 2 feet.

The converter runs in your browser and works offline once the page has loaded.

A height in feet and inches

Inputs: Length (or feet and inches like 5'10"): 5'10"; From: metres (m); To: centimetres (cm)

Type 5'10" and convert to centimetres (the From choice of metres, m, is ignored for feet-and-inch input). 70 inches × 2.54 is exactly 177.8 cm.

Result: 70 inches (5'10") = 177.8 centimetres In feet and inches: 5′ 10″ Also: 1,778 mm, 1.778 m, 0.001778 km, 5.833333 ft, 1.944444 yd, 0.0011048 mi

One mile in kilometres

Inputs: Length (or feet and inches like 5'10"): 1; From: miles (mi); To: kilometres (km)

Enter 1 and convert miles to kilometres. The unit name stays singular for 1, and the exact 1,609.344 m definition gives 1.609344 km.

Result: 1 mile = 1.609344 kilometres In feet and inches: 5280′ 0″ Also: 1,609,344 mm, 160,934.4 cm, 1,609.344 m, 63,360 in, 5,280 ft, 1,760 yd

100 metres in feet

Inputs: Length (or feet and inches like 5'10"): 100; From: metres (m); To: feet (ft)

Enter 100 and convert metres to feet. The result is 328.08 feet, also shown as 328 feet and just over 1 inch.

Result: 100 metres = 328.08399 feet In feet and inches: 328′ 1.01″ Also: 100,000 mm, 10,000 cm, 0.1 km, 3,937.007874 in, 109.36133 yd, 0.062137 mi

How many feet are in a metre?

About 3.281.

How do I convert feet and inches to cm?

Type them like 5'10"; it is (feet × 12 + inches) × 2.54.

How many km is a mile?

1.609344 km exactly.

Is an inch exactly 2.54 cm?

Yes, by definition since 1959.

What is a nautical mile?

1,852 metres.

Does it work offline?

Yes, once loaded.