km · mi · m · ft · in
Length converter
One mile is exactly 1.609344 kilometres, and one foot is exactly 0.3048 metres. Enter a length, pick a unit and read it in all eleven units at once.
- 1 km = 0.6213712 mi
- 1 mi = 1.609344 km
The result and the table below it update as you type. Only the printed figure is rounded, to six significant digits, so a rounded value is never carried into the next conversion.
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At a glance
- Price
- No charge
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- None needed
- Upload
- Not applicable — you type a value, nothing is sent anywhere
- Units
- Metre, kilometre, centimetre, millimetre, micrometre, nanometre, mile, yard, foot, inch and nautical mile
- Precision
- Exact factors, printed to six significant digits
- Works on
- Any modern browser
Common length conversions
These tables are computed from the same factors as the converter. Read each one left to right: the first column is the value you start with and the second is its equivalent.
| km | mi |
|---|---|
| 1 | 0.621371 |
| 5 | 3.10686 |
| 10 | 6.21371 |
| 50 | 31.0686 |
| 100 | 62.1371 |
| mi | km |
|---|---|
| 1 | 1.60934 |
| 5 | 8.04672 |
| 10 | 16.0934 |
| 50 | 80.4672 |
| 100 | 160.934 |
| m | ft |
|---|---|
| 1 | 3.28084 |
| 5 | 16.4042 |
| 10 | 32.8084 |
| 50 | 164.042 |
| 100 | 328.084 |
| ft | m |
|---|---|
| 1 | 0.3048 |
| 5 | 1.524 |
| 10 | 3.048 |
| 50 | 15.24 |
| 100 | 30.48 |
| cm | in |
|---|---|
| 1 | 0.393701 |
| 5 | 1.9685 |
| 10 | 3.93701 |
| 50 | 19.685 |
| 100 | 39.3701 |
| in | cm |
|---|---|
| 1 | 2.54 |
| 5 | 12.7 |
| 10 | 25.4 |
| 50 | 127 |
| 100 | 254 |
Length units and their exact size
| Unit | Symbol | Exact size |
|---|---|---|
| Metre | m | 1 m = 1 m |
| Kilometre | km | 1 km = 1000 m |
| Centimetre | cm | 1 cm = 0.01 m |
| Millimetre | mm | 1 mm = 0.001 m |
| Micrometre | µm | 1 µm = 0.000001 m |
| Nanometre | nm | 1 nm = 1e-9 m |
| Mile | mi | 1 mi = 1609.344 m |
| Yard | yd | 1 yd = 0.9144 m |
| Foot | ft | 1 ft = 0.3048 m |
| Inch | in | 1 in = 0.0254 m |
| Nautical mile | nmi | 1 nmi = 1852 m |
How to convert a length
Enter the length
Type a number in the first field. Negative values and decimals are accepted, so 12.5 and −3 both work.
Pick the two units
Choose the unit you have in the first menu and the unit you want in the second. The swap button reverses the two.
Read the table
The large figure is your answer. The table lists the same length in every other unit, so you can copy the one you need without converting again.
How length conversion works
Every unit on this page is defined from the metre. A kilometre is 1000 m, a centimetre 0.01 m and a millimetre 0.001 m. The imperial units are fixed by the 1959 international yard and pound agreement: a yard is exactly 0.9144 m, so a foot is 0.3048 m, an inch 25.4 mm and a mile 1609.344 m. A nautical mile is exactly 1852 m.
A conversion is a multiplication and a division: the value times the source unit's size in metres, divided by the target unit's. Kilometres to miles is value × 1000 ÷ 1609.344, which is value × 0.621371 to six digits. Because the factors are exact, the only rounding is in the figure printed. The US survey foot, which differs from the international foot by about two parts per million, is not offered.
Length conversion questions
How many kilometres are in a mile?
One mile is exactly 1.609344 kilometres. Multiply miles by 1.609344 to get kilometres, or divide kilometres by 1.609344 to get miles: 10 miles is 16.09344 km, and 10 km is 6.21371 mi.
How many centimetres are in an inch?
One inch is exactly 2.54 centimetres, or 25.4 millimetres. So 12 inches, one foot, is 30.48 cm, and 6 feet is 182.88 cm.
What is the difference between a nautical mile and a mile?
A nautical mile is exactly 1852 metres, about 1.15 statute miles, while a statute mile is 1609.344 metres. Nautical miles are used at sea and in aviation, and the unit was originally defined as one minute of latitude.
Do my numbers leave my device?
No. The unit tables are part of the page and the arithmetic runs in your browser, so nothing you type is sent anywhere. With the page already loaded, the converter also works offline.
How precise are the results?
Results are computed in double precision from exact factors and printed to six significant digits; the unit table shows twelve. Values below 1e-6 or at 1e15 and above switch to exponent form so they stay readable.