Length Converter
Convert length and distance between metric, imperial and scientific units. Pick two units, type a value and see the answer at once.
Select two units to see the conversion factor.
This tool converts length only. Square units (area) and cubic units (volume) are not length units. Use the Area Converter or Volume Converter for those.
Length Formula
Every length unit is a fixed part of the meter. To convert, find the size of both units in meters, then divide: result = value × (size of source unit ÷ size of target unit). These sizes are exact by definition: 1 inch = 0.0254 m, 1 foot = 0.3048 m, 1 yard = 0.9144 m, 1 mile = 1,609.344 m and 1 nautical mile = 1,852 m. No rounding is done until the final answer is shown.
What Is Length?
Length tells you how far it is from one point to another. The base unit in the SI (metric) system is the meter. Height, width, depth, distance and thickness are all lengths.
This converter covers three groups of units. Metric units run from kilometer and meter down to millimeter, micrometer and nanometer. Imperial and US units include the inch, foot, yard and mile, plus older survey units such as the chain, rod and furlong. Special units are used in other fields, for example the nautical mile at sea, the point and pica in printing, the angstrom in chemistry and the light year and parsec in astronomy.
US survey units. Since 1959 the international foot is exactly 0.3048 m. The older US survey foot is 1200/3937 m. The two differ by about 2 parts per million. Over short distances you will not notice, but over large land surveys the gap adds up. That is why both are listed and labelled separately.
Supported Units
This converter supports the following 66 length units. The last column gives the size of each unit in meters.
| Unit | Symbol | Value in m |
|---|---|---|
| Exameter | Em | 1e+18 |
| Petameter | Pm | 1e+15 |
| Terameter | Tm | 1e+12 |
| Gigameter | Gm | 1,000,000,000 |
| Megameter | Mm | 1,000,000 |
| Kilometer | km | 1,000 |
| Hectometer | hm | 100 |
| Dekameter | dam | 10 |
| Meter | m | 1 |
| Decimeter | dm | 0.1 |
| Centimeter | cm | 0.01 |
| Millimeter | mm | 0.001 |
| Micrometer | µm | 1e-6 |
| Nanometer | nm | 1e-9 |
| Picometer | pm | 1e-12 |
| Femtometer | fm | 1e-15 |
| Attometer | am | 1e-18 |
| Micron | µ | 1e-6 |
| Angstrom | Å | 1e-10 |
| Inch | in | 0.0254 |
| Foot | ft | 0.3048 |
| Yard | yd | 0.9144 |
| Mile | mi | 1,609.344 |
| Kiloyard | kyd | 914.4 |
| Mil (thou) | mil | 2.54e-5 |
| Microinch | µin | 2.54e-8 |
| Centiinch (caliber) | cin | 0.000254 |
| Barleycorn | barleycorn | 0.008466666667 |
| Nail (cloth) | nail | 0.05715 |
| Finger (cloth) | finger | 0.1143 |
| Hand | hand | 0.1016 |
| Span (cloth) | span | 0.2286 |
| Cubit (UK) | cubit | 0.4572 |
| Ell | ell | 1.143 |
| Fathom | fath | 1.8288 |
| Link | li | 0.201168 |
| Rod (pole, perch) | rd | 5.0292 |
| Chain | ch | 20.1168 |
| Furlong | fur | 201.168 |
| League (statute) | lea | 4,828.032 |
| Foot (US survey) | ft (US survey) | 0.3048006096 |
| Inch (US survey) | in (US survey) | 0.0254000508 |
| Link (US survey) | li (US survey) | 0.2011684023 |
| Rod (US survey) | rd (US survey) | 5.029210058 |
| Chain (US survey) | ch (US survey) | 20.11684023 |
| Furlong (US survey) | fur (US survey) | 201.1684023 |
| Fathom (US survey) | fath (US survey) | 1.828803658 |
| Mile (US survey) | mi (US survey) | 1,609.347219 |
| Nautical mile (international) | nmi | 1,852 |
| Nautical mile (UK Admiralty, historic) | NM (UK) | 1,853.184 |
| Nautical league (international) | nlea | 5,556 |
| Russian archin | archin | 0.7112 |
| Pica | pica | 0.004233333333 |
| Point (desktop publishing) | pt | 0.0003527777778 |
| Twip | twip | 1.763888889e-5 |
| Bohr radius | a₀ | 5.291772105e-11 |
| Classical electron radius | rₑ | 2.81794032e-15 |
| Planck length | ℓP | 1.616255e-35 |
| Astronomical unit | AU | 149,597,870,700 |
| Light year | ly | 9.460730473e+15 |
| Parsec | pc | 3.085677581e+16 |
| Kiloparsec | kpc | 3.085677581e+19 |
| Megaparsec | Mpc | 3.085677581e+22 |
| Earth’s equatorial radius (WGS 84) | R⊕ eq. | 6,378,137 |
| Earth’s polar radius (WGS 84) | R⊕ pol. | 6,356,752.314 |
| Sun’s radius (IAU nominal) | R☉ | 695,700,000 |
How to Use the Length Converter
- Type the length in the value box. Decimals and scientific notation such as 0.0025 or 2.5e-3 are accepted.
- Choose the From unit and the To unit.
- The result appears instantly, or press Convert Now. Very large or very small results are shown in scientific notation.
- Use Swap Units to reverse the conversion, Copy Result to copy the answer, open Show this value in all units for a full list, and Clear to start again.
Step-by-step by hand
- Find the size of each unit in the common base unit (m): 1 ft = 0.3048 m and 1 cm = 0.01 m.
- Divide the source size by the target size to get the conversion factor: 0.3048 ÷ 0.01 = 30.48, so 1 ft = 30.48 cm.
- Multiply by your value: 6 ft × 30.48 = 182.88 cm.
Length cannot be negative here, so enter zero or a positive number. Very large or very small answers are shown in scientific notation.
Common Length Conversions
- Height: 6 ft equals 182.88 cm, and 180 cm equals 5.905511811 ft.
- Road distance: 10 km equals 6.213711922 miles, and 26.2 miles equals 42.1648128 km.
- Screen or pipe size: 32 inches equals 81.28 cm.
- Sea distance: 100 nautical miles equals 185.2 km.
- Sports field: 100 yards equals 91.44 m.
- Tiny size: 500 nm equals 0.5 µm.
- Astronomy: 1 light year equals 9.460730473e+12 km.
Meter to Other Length Units
Quick reference for frequently used values
| m | ft | in | yd |
|---|---|---|---|
| 1 | 3.280839895 | 39.37007874 | 1.093613298 |
| 2 | 6.56167979 | 78.74015748 | 2.187226597 |
| 5 | 16.40419948 | 196.8503937 | 5.468066492 |
| 10 | 32.80839895 | 393.7007874 | 10.93613298 |
| 50 | 164.0419948 | 1,968.503937 | 54.68066492 |
| 100 | 328.0839895 | 3,937.007874 | 109.3613298 |
| 500 | 1,640.419948 | 19,685.03937 | 546.8066492 |
| 1,000 | 3,280.839895 | 39,370.07874 | 1,093.613298 |
Where and Why This Conversion Is Used
- Building and DIY: plans use meters in most countries and feet and inches in the US.
- Travel and sport: road signs in miles or kilometers, running tracks in meters, golf in yards.
- Shipping and aviation: nautical miles for sea and air routes.
- Science and engineering: micrometers, nanometers and angstroms for small structures.
- Printing and design: points, picas and inches.
Important Limitations
- The tool changes units only. It does not measure distance on a map or between two places.
- Astronomical and atomic units depend on published constants (for example the Bohr radius or Earth radius). Those constants are measured values and may be updated by science bodies.
- Units such as ancient cubits or regional “varas” had different sizes in different places and times. They are left out because they have no single verified size.
- The international mile and the US survey mile are different units. Choose the one your document names.