Length Converter
Type a length into any of the 12 units and every other unit updates at once. Enter heights as feet + inches, see the result to the nearest 1/16 inch, and copy any value with one click.
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Common lengths (click to load)
Formula with your numbers
Length conversion table
| From | To |
|---|
20 rows. Click a row to load it into the converter.
How to use the Length Converter
- Type a length into any unit box, for example 5.5 in Feet or 170 in Centimeters.
- For heights, use the Feet + inches row: enter 5 and 9 to see 175.26 cm.
- Set the precision or switch on scientific notation for very large or tiny lengths.
- Copy a value with its Copy button, or press Copy all results for the full list.
- Build a table below by choosing from/to units, a start value and a step.
How length conversion works
Every unit here is defined as an exact multiple of the meter, so the converter turns your number into meters and then into each target unit: result = value × (meters per source unit) ÷ (meters per target unit). For example, 6 ft → 6 × 0.3048 = 1.8288 m → 1.8288 ÷ 0.0254 = 72 in.
Imperial units chain together in whole numbers (12 inches per foot, 3 feet per yard, 1,760 yards per mile), while metric units step by powers of ten. That is why feet-and-inches results are shown both as decimals and as a combined “5′ 9 3/8″” style reading.
Exact length equivalents
| Unit | Imperial equivalent | Metric equivalent |
|---|---|---|
| 1 inch | 2.54 cm (exact) | 25.4 mm |
| 1 foot | 12 in | 30.48 cm (exact) |
| 1 yard | 3 ft = 36 in | 0.9144 m (exact) |
| 1 mile | 5,280 ft = 1,760 yd | 1.609344 km (exact) |
| 1 nautical mile | 6,076.12 ft ≈ 1.15078 mi | 1,852 m (exact) |
| 1 meter | 39.3701 in ≈ 3.28084 ft | 100 cm |
| 1 kilometer | 0.621371 mi | 3,280.84 ft |
| 1 mil (thou) | 0.001 in | 25.4 µm (exact) |
| 1 micron (µm) | 0.03937 mil | 0.001 mm |
| 1 astronomical unit | 92,955,807 mi | 149,597,870.7 km (exact) |
Tips
- Tape-measure fractions: the 1/16-inch reading matches most US tape measures; round to 1/8 for rough carpentry.
- Running distances: a 5K is 3.107 miles and a marathon is 26.219 miles (42.195 km).
- Aviation and boating: use nautical miles with knots; one knot is one nautical mile per hour.
- Manufacturing: thicknesses in mils convert to microns by multiplying by 25.4 (4 mil = 101.6 µm).
Frequently asked questions
How many centimeters are in an inch?
Exactly 2.54 cm. The inch was defined as 25.4 mm by the 1959 international yard and pound agreement, so every inch, foot, yard and mile conversion is exact.
How do I convert feet and inches to centimeters?
Multiply the feet by 12, add the inches, then multiply by 2.54. For example, 5 ft 9 in = 69 in × 2.54 = 175.26 cm. The Feet + inches row in the converter does this for you.
How is a nautical mile different from a mile?
A nautical mile is exactly 1,852 meters (about 1.15078 statute miles). It is based on one minute of latitude and is used in sea and air navigation, where speeds are given in knots.
What is a mil, and is it the same as a millimeter?
No. A mil (or thou) is one thousandth of an inch, 25.4 micrometers. It is used for plastic film, coatings and wire. A millimeter is about 39.37 mils.
What is a micron?
Micron is the common name for the micrometer (µm), one millionth of a meter or one thousandth of a millimeter. It is used for filters, fibers and machining tolerances.
How long is an astronomical unit?
Exactly 149,597,870,700 meters (about 93 million miles) by the IAU 2012 definition, roughly the average distance between Earth and the Sun.
Does the converter use the US survey foot?
No. It uses the international foot of exactly 0.3048 m. The US survey foot (1200/3937 m) was officially retired at the end of 2022, and the two differ by only 2 parts per million.
Are all the tools on FreeToolCabin tested for quality and accuracy?
Yes! Every tool on our site undergoes automated Q/A testing in real browser environments to ensure high precision, correct output, and zero errors. If you happen to spot a bug or have a suggestion, please contact us at [email protected] and our team will review it right away.