📏 Length Converter

Enter a value and pick its unit — every other unit updates instantly below. Covers metric and imperial length and distance units.

Value

Unit

Exact factors, not approximations

Since 1959 every imperial length has had an exact metric definition, so none of these numbers are measurements - they are agreements. The tool converts your value to metres, then divides into the other eight units:

1 inch          = 2.54 cm exactly
1 foot          = 0.3048 m      = 12 in
1 yard          = 0.9144 m      = 3 ft
1 mile          = 1609.344 m    = 5,280 ft
1 nautical mile = 1852 m exactly = 1.15078 miles

To convert a height, work in inches first. 5 ft 10 in is (5 × 12) + 10 = 70 in, and 70 × 2.54 = 177.8 cm. Going back, 180 cm is 70.866 in, which is 5 ft 10.87 in.

The conversions people look up

From	Equals	And
1 in	2.54 cm	25.4 mm
1 ft	30.48 cm	0.3048 m
1 m	3.28084 ft	39.3701 in
1 km	0.621371 mi	3,280.84 ft
1 mi	1.609344 km	1,760 yd
1 nmi	1.852 km	6,076.12 ft

Two worth memorising: a metre is a yard plus about 9%, and a 5 km run is 3.107 miles.

A nautical mile is not a rounded statute mile. It was set at one minute of latitude, which is why 60 of them make a degree, and it is the reason a knot is one nautical mile per hour rather than 1.15 mph.

Frequently asked questions

How many cm are in an inch?

Exactly 2.54 cm, by international definition rather than measurement. So 12 inches is 30.48 cm, and to go from cm to inches you divide by 2.54.

How many feet is 1 metre?

3.28084 feet, which is 3 feet and 3.37 inches. A quick mental version is to add about 10% to the metre figure and call it yards: 100 m is roughly 109 yards, and exactly 109.361.

Is a nautical mile longer than a mile?

Yes. A nautical mile is 1,852 m against 1,609.344 m for a statute mile, so it is 15.08% longer. Shipping and aviation use it because it maps directly onto latitude on a chart.