Length Converter
Meters, feet, inches, miles — all of them at once.
1 cm in every unit
| Millimeters | 10 mm |
| Centimeters | 1 cm |
| Meters | 0.01 m |
| Kilometers | 0.00001 km |
| Inches | 0.393701 in |
| Feet | 0.0328084 ft |
| Yards | 0.0109361 yd |
| Miles | 0.0000062137 mi |
| Nautical miles | 0.0000053996 nmi |
How this was worked outmeters → in 0.3937007874
- 1 cm → meters0.01
- meters → in0.3937007874
An inch is exactly 25.4 millimetres by definition, so every length conversion here is exact rather than approximate.
Guide: An inch is exactly 25.4 millimeters2 min read
An inch is exactly 25.4 millimeters
Not approximately. Since the international yard and pound agreement of 1959, the inch is defined as 25.4 mm exactly, and every imperial length here follows from that: a foot is twelve of them, a yard is three feet, a mile is 1,760 yards.
That is why the numbers in this converter are exact rather than rounded constants. A foot is 0.3048 m with nothing after it.
The nautical mile is not an ordinary mile
It is 1,852 meters, against 1,609 for a statute mile — about fifteen per cent longer. The reason is that it was defined by the planet rather than by convention: one nautical mile is one minute of latitude, so a degree of latitude is sixty of them.
That property is why ships and aircraft still use it. On a chart, distance and angle are the same measurement.
The US survey foot is gone
For most of the twentieth century the United States kept a second, very slightly longer foot for land surveying — larger by two parts per million. Harmless over a room, and a difference of several centimeters across a state.
It was retired at the end of 2022. Only the international foot remains, and that is the one used here. If you are reading old survey documents, the distinction may still matter to you.
Nothing is sent anywhere
Every conversion on this page is arithmetic done in your own browser. No request is made, nothing is stored between visits, and the page keeps working with the connection switched off — which is a reasonable way to check the claim.
Frequently asked questions
How do I convert my height to feet and inches?
Enter your height in centimeters and read the feet row, then take the fractional part and convert that to inches. 175 cm is 5.74 feet, and 0.74 of a foot is a little under nine inches — so 5 feet 9 inches. The full table makes the second step visible rather than something you have to do in your head.
Why are there so many decimal places?
Because a conversion is rarely exact in the unit you are converting to, and rounding early is how errors accumulate. Values are shown to ten significant figures and switch to exponent notation only when a decimal string would be unreadable. Round at the end, to whatever your work actually needs.
Which units are exact and which are defined?
Every imperial unit here is defined in terms of the metric one, exactly. The metric units are defined against the meter, which is itself defined by the speed of light. Nothing in this table is an approximation somebody measured.
Is anything sent anywhere?
No. The arithmetic happens in this tab and nothing is transmitted or stored. The page works with the connection switched off.