Length converter — metres, feet, inches, yards and miles

Heights in feet and inches, running distances in kilometres, drawings dimensioned in millimetres. Length is the family people mix most, and mixing is exactly what this page is built for.

How to use it

1
Type into any row — say m or ft. The results appear immediately, no button needed.
2
Need a combined figure? Fill in two rows, for example m and in, and they are added together before converting.
3
Set how many digits you want (4–12) and click a result to copy the plain number.

Exact conversion factors

These are the definitions the calculator uses. Nothing here is rounded for convenience — where a value is exact by definition, it says so.

1 in = 25.4 mm exactly · 1 ft = 0.3048 m exactly · 1 yd = 0.9144 m exactly
1 m = 3.28083990 ft = 39.3700787 in
1 mi = 1609.344 m = 5280 ft · 1 nmi = 1852 m exactly
1 km = 0.621371192 mi

Formulam = ft × 0.3048 · ft = m ÷ 0.3048 · cm = in × 2.54 · km = mi × 1.609344

Length conversion table — every unit

One of each unit, converted into the three units people ask for most.

Unit	m	ft	in
1 km	1 000 m	3 280.84 ft	39 370.1 in
1 m	1 m	3.28084 ft	39.3701 in
1 dm	0.1 m	0.328084 ft	3.93701 in
1 cm	0.01 m	0.0328084 ft	0.393701 in
1 mm	0.001 m	0.00328084 ft	0.0393701 in
1 µm	0.000001 m	0.00000328084 ft	0.0000393701 in
1 nm	1.00000×10^-9 m	0.00000000328084 ft	0.0000000393701 in
1 mi	1 609.34 m	5 280 ft	63 360 in
1 nmi	1 852 m	6 076.12 ft	72 913.4 in
1 yd	0.9144 m	3 ft	36 in
1 ft	0.3048 m	1 ft	12 in
1 in	0.0254 m	0.0833333 ft	1 in

m → ft, in — quick values

m	ft	in
0.5 m	1.64042 ft	19.685 in
1 m	3.28084 ft	39.3701 in
2 m	6.56168 ft	78.7402 in
3 m	9.84252 ft	118.11 in
5 m	16.4042 ft	196.85 in
10 m	32.8084 ft	393.701 in
20 m	65.6168 ft	787.402 in
25 m	82.021 ft	984.252 in
50 m	164.042 ft	1 968.5 in
100 m	328.084 ft	3 937.01 in
250 m	820.21 ft	9 842.52 in
1 000 m	3 280.84 ft	39 370.1 in

How this converter works

Type 5 in the foot row and 9 in the inch row: the result is 175.26 cm, because both rows feed the same total. That saves the usual two-step dance of converting feet first and inches second and adding them by hand.

Metric and imperial rows are linked by exact definitions — an inch is 25.4 mm, a yard is 0.9144 m, a statute mile is 1609.344 m. The nautical mile is a different animal: 1852 m exactly, tied to a minute of latitude rather than to the yard, which is why sea and air distances never match road distances.

Notes and abbreviations

mi — statute mile, 5280 ft; nmi — nautical mile, 1852 m
µm — micrometre, one thousandth of a millimetre (a human hair is roughly 70 µm)
nm — nanometre, the scale used for chip manufacturing and light wavelengths

Questions

How tall is 6 ft 2 in in centimetres?

Enter 6 in the foot row and 2 in the inch row — 187.96 cm exactly.

Why is a nautical mile longer than a mile?

It was defined from the Earth itself: one minute of arc along a meridian, rounded to 1852 m. A statute mile of 1609.344 m comes from Roman paces instead.

Can I convert screen sizes with this?

Yes — a 27-inch monitor is 68.58 cm measured diagonally. Type 27 in the inch row.