Length Converter
Convert between millimeters, centimeters, meters, kilometers, inches, feet, yards, and miles.
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Enter a value to see the conversion.
How it works
How to use
Enter a length, choose the source and target units, then read the result immediately.
Method
Values are converted through meters. Defined imperial relationships use the exact international inch of 0.0254 meters.
Example
1 kilometer equals approximately 0.621371 miles.
Length conversion reference
The table puts the eight units available in SnakTool on one scale. Each row starts with one unit and shows its equivalent in the other supported units. Rounded values are marked with ≈; terminating exact equivalents are shown without it.
| 1 unit | mm | cm | m | km | in | ft | yd | mi |
|---|---|---|---|---|---|---|---|---|
| 1 mm | 1 | 0.1 | 0.001 | 0.000001 | ≈ 0.0393701 | ≈ 0.00328084 | ≈ 0.00109361 | ≈ 0.000000621371 |
| 1 cm | 10 | 1 | 0.01 | 0.00001 | ≈ 0.393701 | ≈ 0.0328084 | ≈ 0.0109361 | ≈ 0.00000621371 |
| 1 m | 1,000 | 100 | 1 | 0.001 | ≈ 39.3701 | ≈ 3.28084 | ≈ 1.09361 | ≈ 0.000621371 |
| 1 km | 1,000,000 | 100,000 | 1,000 | 1 | ≈ 39,370.1 | ≈ 3,280.84 | ≈ 1,093.61 | ≈ 0.621371 |
| 1 in | 25.4 | 2.54 | 0.0254 | 0.0000254 | 1 | ≈ 0.0833333 | ≈ 0.0277778 | ≈ 0.0000157828 |
| 1 ft | 304.8 | 30.48 | 0.3048 | 0.0003048 | 12 | 1 | ≈ 0.333333 | ≈ 0.000189394 |
| 1 yd | 914.4 | 91.44 | 0.9144 | 0.0009144 | 36 | 3 | 1 | ≈ 0.000568182 |
| 1 mi | 1,609,344 | 160,934.4 | 1,609.344 | 1.609344 | 63,360 | 5,280 | 1,760 | 1 |
Metric on one side, inches and feet on the other
Millimeters, centimeters, meters, and kilometers scale by powers of ten. The other four units use different steps: 12 inches make a foot, 3 feet make a yard, and 1,760 yards make a mile.
The exact bridge between the systems is the international inch: 1 in = 2.54 cm. From it follow 1 ft = 0.3048 m, 1 yd = 0.9144 m, and 1 mi = 1.609344 km.
A single value must already be in one unit
The converter reads one finite number in the unit selected beside it. Decimal and scientific notation are accepted, but a mixed measurement such as 5 ft 8 in is not parsed as two quantities.
For a mixed measurement, combine it first. Five feet eight inches is 68 inches, or 5.666666... feet. The same distinction matters for decimal feet: 5.5 ft is 5 ft 6 in, not 5 ft 5 in.
Frequently asked questions about Length Converter
Is 1 inch exactly 2.54 centimeters?
Yes. The international inch is defined as exactly 0.0254 meter, so it is exactly 2.54 centimeters.
Why are some values in the reference table approximate?
Some exact unit relationships produce repeating or long decimal expansions when expressed in another unit. The table shortens those values for reference; the converter calculates from its stored unit factors.
How many centimeters are in an inch?
One inch is exactly 2.54 centimeters.
How many feet are in a mile?
One mile is exactly 5,280 feet.
How many yards are in a mile?
One mile is exactly 1,760 yards.
How many inches are in a foot?
One foot is exactly 12 inches.
How many kilometers are in a mile?
One mile is exactly 1.609344 kilometers.
How many miles are in a kilometer?
One kilometer is approximately 0.621371 miles.
What does 5.5 feet mean in feet and inches?
The decimal 0.5 foot equals 6 inches, so 5.5 ft means 5 ft 6 in.
Can I enter scientific notation?
Yes. A finite numeric value such as 1e6 is accepted in the selected length unit.
Can this convert square or cubic units?
No. Length, area, and volume use different dimensional factors; use the corresponding converter for square or cubic units.