Category · Unit Hub
Length Converters
Every length unit in one place — 144 units, 5,094 conversions, grouped by family with a live calculator on the right. Use the popular shortcuts and matrix below for the most common pairs, or scroll the directory to find any unit and its full set of conversions.
Popular length converters
The 24 most-searched length pairs. Tap any pair to open its dedicated converter.
Centimeters to Meters1 cm = 0.01 m
Meters to Centimeters1 m = 100 cm
Centimeters to Inches1 cm = 0.393701 in
Inches to Centimeters1 in = 2.54 cm
Meters to Feet1 m = 3.28084 ft
Feet to Meters1 ft = 0.3048 m
Kilometers to Miles1 km = 0.621371 mi
Miles to Kilometers1 mi = 1.609344 km
Millimeters to Inches1 mm = 0.0393701 in
Inches to Millimeters1 in = 25.4 mm
Meters to Inches1 m = 39.3701 in
Inches to Meters1 in = 0.0254 m
Yards to Meters1 yd = 0.9144 m
Meters to Yards1 m = 1.09361 yd
Feet to Centimeters1 ft = 30.48 cm
Centimeters to Feet1 cm = 0.0328084 ft
Millimeters to Centimeters1 mm = 0.1 cm
Centimeters to Millimeters1 cm = 10 mm
Kilometers to Meters1 km = 1000 m
Meters to Kilometers1 m = 0.001 km
Feet to Inches1 ft = 12 in
Inches to Feet1 in = 0.0833333 ft
Nautical Miles to Kilometers1 nmi = 1.852 km
Micrometers to Millimeters1 μm = 0.001 mm
Conversion matrix
The 10 most-used length units, every pair as a clickable link.
About length measurement
Length is the most fundamental of physical dimensions — every other geometric quantity (area, volume, displacement, density) reduces to length raised to some power. In the International System of Units (SI), the meter is the base unit of length, and every other SI length unit (nanometer, millimeter, centimeter, kilometer) is a power-of-ten multiple of the meter. The Imperial system, used officially only in the United States, Liberia and Myanmar, builds on the yard (defined since 1959 as exactly 0.9144 meters), with the inch, foot and mile derived from it.
Modern length definition is anchored to a universal physical constant: since 2019, the meter is defined by fixing the speed of light in vacuum to exactly 299,792,458 m/s. This means every length conversion on this site is exact to the precision shown — no measurement uncertainty, only rounding. The directory below covers all 144 length units this site supports, from the Planck length to the megaparsec.
All length units
Tap any unit to expand its full list of outgoing conversions. Units are grouped by family.
Metric / SI
Attometer (am) — 15 conversions
Attometer to CentimeterAttometer to DecimeterAttometer to DekameterAttometer to FemtometerAttometer to FootAttometer to HectometerAttometer to InchAttometer to KilometerAttometer to MeterAttometer to MicrometerAttometer to MicronAttometer to MileAttometer to MillimeterAttometer to NanometerAttometer to Yard
Femtometer (fm) — 15 conversions
Femtometer to AttometerFemtometer to CentimeterFemtometer to DecimeterFemtometer to DekameterFemtometer to FootFemtometer to HectometerFemtometer to InchFemtometer to KilometerFemtometer to MeterFemtometer to MicrometerFemtometer to MicronFemtometer to MileFemtometer to NanometerFemtometer to PicometerFemtometer to Yard
Picometer (pm) — 8 conversions
Nanometer (nm) — 18 conversions
Nanometer to AttometerNanometer to CentimeterNanometer to DecimeterNanometer to DekameterNanometer to FemtometerNanometer to FootNanometer to HectometerNanometer to InchNanometer to KilometerNanometer to MeterNanometer to MicrometerNanometer to MicronNanometer to MilNanometer to MileNanometer to MillimeterNanometer to Nautical MileNanometer to PicometerNanometer to Yard
Micrometer (um) — 17 conversions
Micrometer to AttometerMicrometer to CentimeterMicrometer to DecimeterMicrometer to DekameterMicrometer to FemtometerMicrometer to FootMicrometer to HectometerMicrometer to InchMicrometer to KilometerMicrometer to MeterMicrometer to MicronMicrometer to MilMicrometer to MileMicrometer to MillimeterMicrometer to NanometerMicrometer to Nautical MileMicrometer to Yard
Micron (micron) — 15 conversions
Millimeter (mm) — 37 conversions
Millimeter to Bohr RadiusMillimeter to Planck LengthMillimeter to AngstromMillimeter to AttometerMillimeter to BarleycornMillimeter to CaliberMillimeter to CentiinchMillimeter to CentimeterMillimeter to ChainMillimeter to EllMillimeter to FermiMillimeter to FingerMillimeter to FootMillimeter to FurlongMillimeter to HandMillimeter to InchMillimeter to KiloparsecMillimeter to KiloyardMillimeter to LeagueMillimeter to Light YearMillimeter to LinkMillimeter to MicroinchMillimeter to MicrometerMillimeter to MilMillimeter to MileMillimeter to NailMillimeter to NanometerMillimeter to Nautical MileMillimeter to ParsecMillimeter to PerchMillimeter to PoleMillimeter to RodMillimeter to RopeMillimeter to SpanMillimeter to TwipMillimeter to X-unitMillimeter to Yard
Centimeter (cm) — 44 conversions
Centimeter to Bohr RadiusCentimeter to Planck LengthCentimeter to AngstromCentimeter to AttometerCentimeter to BarleycornCentimeter to CaliberCentimeter to CentiinchCentimeter to ChainCentimeter to DecimeterCentimeter to DekameterCentimeter to EllCentimeter to FemtometerCentimeter to FermiCentimeter to FingerCentimeter to FootCentimeter to FurlongCentimeter to HandCentimeter to HectometerCentimeter to InchCentimeter to KilometerCentimeter to KiloparsecCentimeter to KiloyardCentimeter to LeagueCentimeter to Light YearCentimeter to LinkCentimeter to MeterCentimeter to MicroinchCentimeter to MicrometerCentimeter to MicronCentimeter to MilCentimeter to MileCentimeter to NailCentimeter to NanometerCentimeter to Nautical MileCentimeter to ParsecCentimeter to PerchCentimeter to PicometerCentimeter to PoleCentimeter to RodCentimeter to RopeCentimeter to SpanCentimeter to TwipCentimeter to X-unitCentimeter to Yard
Decimeter (dm) — 17 conversions
Decimeter to AttometerDecimeter to CentimeterDecimeter to DekameterDecimeter to FemtometerDecimeter to FootDecimeter to HectometerDecimeter to InchDecimeter to KilometerDecimeter to MeterDecimeter to MicrometerDecimeter to MicronDecimeter to MilDecimeter to MileDecimeter to MillimeterDecimeter to NanometerDecimeter to Nautical MileDecimeter to Yard
Meter (m) — 45 conversions
Meter to Bohr RadiusMeter to Planck LengthMeter to AngstromMeter to AttometerMeter to BarleycornMeter to CaliberMeter to CentiinchMeter to CentimeterMeter to ChainMeter to DecimeterMeter to DekameterMeter to EllMeter to FemtometerMeter to FermiMeter to FingerMeter to FootMeter to FurlongMeter to HandMeter to HectometerMeter to InchMeter to KilometerMeter to KiloparsecMeter to KiloyardMeter to LeagueMeter to Light YearMeter to LinkMeter to MicroinchMeter to MicrometerMeter to MicronMeter to MilMeter to MileMeter to MillimeterMeter to NailMeter to NanometerMeter to Nautical MileMeter to ParsecMeter to PerchMeter to PicometerMeter to PoleMeter to RodMeter to RopeMeter to SpanMeter to TwipMeter to X-unitMeter to Yard
Dekameter (dam) — 16 conversions
Dekameter to AttometerDekameter to CentimeterDekameter to DecimeterDekameter to FemtometerDekameter to FootDekameter to HectometerDekameter to InchDekameter to KilometerDekameter to MeterDekameter to MicrometerDekameter to MicronDekameter to MileDekameter to MillimeterDekameter to NanometerDekameter to PicometerDekameter to Yard
Hectometer (hm) — 16 conversions
Hectometer to AttometerHectometer to CentimeterHectometer to DecimeterHectometer to DekameterHectometer to FemtometerHectometer to FootHectometer to InchHectometer to KilometerHectometer to MeterHectometer to MicrometerHectometer to MicronHectometer to MileHectometer to MillimeterHectometer to NanometerHectometer to PicometerHectometer to Yard
Kilometer (km) — 44 conversions
Kilometer to Bohr RadiusKilometer to Planck LengthKilometer to AngstromKilometer to AttometerKilometer to BarleycornKilometer to CaliberKilometer to CentiinchKilometer to CentimeterKilometer to ChainKilometer to DecimeterKilometer to DekameterKilometer to EllKilometer to FemtometerKilometer to FermiKilometer to FingerKilometer to FootKilometer to FurlongKilometer to HandKilometer to HectometerKilometer to InchKilometer to KiloparsecKilometer to KiloyardKilometer to LeagueKilometer to Light YearKilometer to LinkKilometer to MeterKilometer to MicroinchKilometer to MicrometerKilometer to MicronKilometer to MilKilometer to MileKilometer to NailKilometer to NanometerKilometer to Nautical MileKilometer to ParsecKilometer to PerchKilometer to PicometerKilometer to PoleKilometer to RodKilometer to RopeKilometer to SpanKilometer to TwipKilometer to X-unitKilometer to Yard
Imperial / US Customary
Microinch (microinch) — 26 conversions
Microinch to BarleycornMicroinch to CaliberMicroinch to CentiinchMicroinch to CentimeterMicroinch to ChainMicroinch to EllMicroinch to FingerMicroinch to FootMicroinch to FurlongMicroinch to HandMicroinch to InchMicroinch to KilometerMicroinch to KiloyardMicroinch to LeagueMicroinch to LinkMicroinch to MeterMicroinch to MilMicroinch to MileMicroinch to MillimeterMicroinch to NailMicroinch to PerchMicroinch to PoleMicroinch to RodMicroinch to RopeMicroinch to SpanMicroinch to Yard
Mil (mil) — 30 conversions
Mil to BarleycornMil to CaliberMil to CentiinchMil to CentimeterMil to ChainMil to DecimeterMil to EllMil to FingerMil to FootMil to FurlongMil to HandMil to InchMil to KilometerMil to KiloyardMil to LeagueMil to LinkMil to MeterMil to MicroinchMil to MicrometerMil to MileMil to MillimeterMil to NailMil to NanometerMil to Nautical MileMil to PerchMil to PoleMil to RodMil to RopeMil to SpanMil to Yard
Caliber (caliber) — 26 conversions
Caliber to BarleycornCaliber to CentiinchCaliber to CentimeterCaliber to ChainCaliber to EllCaliber to FingerCaliber to FootCaliber to FurlongCaliber to HandCaliber to InchCaliber to KilometerCaliber to KiloyardCaliber to LeagueCaliber to LinkCaliber to MeterCaliber to MicroinchCaliber to MilCaliber to MileCaliber to MillimeterCaliber to NailCaliber to PerchCaliber to PoleCaliber to RodCaliber to RopeCaliber to SpanCaliber to Yard
Centiinch (centiinch) — 26 conversions
Centiinch to BarleycornCentiinch to CaliberCentiinch to CentimeterCentiinch to ChainCentiinch to EllCentiinch to FingerCentiinch to FootCentiinch to FurlongCentiinch to HandCentiinch to InchCentiinch to KilometerCentiinch to KiloyardCentiinch to LeagueCentiinch to LinkCentiinch to MeterCentiinch to MicroinchCentiinch to MilCentiinch to MileCentiinch to MillimeterCentiinch to NailCentiinch to PerchCentiinch to PoleCentiinch to RodCentiinch to RopeCentiinch to SpanCentiinch to Yard
Barleycorn (barleycorn) — 26 conversions
Barleycorn to CaliberBarleycorn to CentiinchBarleycorn to CentimeterBarleycorn to ChainBarleycorn to EllBarleycorn to FingerBarleycorn to FootBarleycorn to FurlongBarleycorn to HandBarleycorn to InchBarleycorn to KilometerBarleycorn to KiloyardBarleycorn to LeagueBarleycorn to LinkBarleycorn to MeterBarleycorn to MicroinchBarleycorn to MilBarleycorn to MileBarleycorn to MillimeterBarleycorn to NailBarleycorn to PerchBarleycorn to PoleBarleycorn to RodBarleycorn to RopeBarleycorn to SpanBarleycorn to Yard
Inch (in) — 43 conversions
Inch to Bohr RadiusInch to Planck LengthInch to AngstromInch to AttometerInch to BarleycornInch to CaliberInch to CentiinchInch to CentimeterInch to ChainInch to DecimeterInch to DekameterInch to EllInch to FemtometerInch to FermiInch to FingerInch to FootInch to FurlongInch to HandInch to HectometerInch to KilometerInch to KiloparsecInch to KiloyardInch to LeagueInch to Light YearInch to LinkInch to MeterInch to MicroinchInch to MicrometerInch to MicronInch to MilInch to MileInch to NailInch to NanometerInch to Nautical MileInch to ParsecInch to PerchInch to PoleInch to RodInch to RopeInch to SpanInch to TwipInch to X-unitInch to Yard
Nail (nail) — 26 conversions
Nail to BarleycornNail to CaliberNail to CentiinchNail to CentimeterNail to ChainNail to EllNail to FingerNail to FootNail to FurlongNail to HandNail to InchNail to KilometerNail to KiloyardNail to LeagueNail to LinkNail to MeterNail to MicroinchNail to MilNail to MileNail to MillimeterNail to PerchNail to PoleNail to RodNail to RopeNail to SpanNail to Yard
Hand (hand) — 26 conversions
Hand to BarleycornHand to CaliberHand to CentiinchHand to CentimeterHand to ChainHand to EllHand to FingerHand to FootHand to FurlongHand to InchHand to KilometerHand to KiloyardHand to LeagueHand to LinkHand to MeterHand to MicroinchHand to MilHand to MileHand to MillimeterHand to NailHand to PerchHand to PoleHand to RodHand to RopeHand to SpanHand to Yard
Finger (finger) — 26 conversions
Finger to BarleycornFinger to CaliberFinger to CentiinchFinger to CentimeterFinger to ChainFinger to EllFinger to FootFinger to FurlongFinger to HandFinger to InchFinger to KilometerFinger to KiloyardFinger to LeagueFinger to LinkFinger to MeterFinger to MicroinchFinger to MilFinger to MileFinger to MillimeterFinger to NailFinger to PerchFinger to PoleFinger to RodFinger to RopeFinger to SpanFinger to Yard
Link (link) — 26 conversions
Link to BarleycornLink to CaliberLink to CentiinchLink to CentimeterLink to ChainLink to EllLink to FingerLink to FootLink to FurlongLink to HandLink to InchLink to KilometerLink to KiloyardLink to LeagueLink to MeterLink to MicroinchLink to MilLink to MileLink to MillimeterLink to NailLink to PerchLink to PoleLink to RodLink to RopeLink to SpanLink to Yard
Span (span) — 26 conversions
Span to BarleycornSpan to CaliberSpan to CentiinchSpan to CentimeterSpan to ChainSpan to EllSpan to FingerSpan to FootSpan to FurlongSpan to HandSpan to InchSpan to KilometerSpan to KiloyardSpan to LeagueSpan to LinkSpan to MeterSpan to MicroinchSpan to MilSpan to MileSpan to MillimeterSpan to NailSpan to PerchSpan to PoleSpan to RodSpan to RopeSpan to Yard
Foot (ft) — 45 conversions
Foot to Bohr RadiusFoot to Planck LengthFoot to AngstromFoot to AttometerFoot to BarleycornFoot to CaliberFoot to CentiinchFoot to CentimeterFoot to ChainFoot to DecimeterFoot to DekameterFoot to EllFoot to FemtometerFoot to FermiFoot to FingerFoot to FurlongFoot to HandFoot to HectometerFoot to InchFoot to KilometerFoot to KiloparsecFoot to KiloyardFoot to LeagueFoot to Light YearFoot to LinkFoot to MeterFoot to MicroinchFoot to MicrometerFoot to MicronFoot to MilFoot to MileFoot to MillimeterFoot to NailFoot to NanometerFoot to Nautical MileFoot to ParsecFoot to PerchFoot to PicometerFoot to PoleFoot to RodFoot to RopeFoot to SpanFoot to TwipFoot to X-unitFoot to Yard
Yard (yd) — 44 conversions
Yard to Bohr RadiusYard to Planck LengthYard to AngstromYard to AttometerYard to BarleycornYard to CaliberYard to CentiinchYard to CentimeterYard to ChainYard to DecimeterYard to DekameterYard to EllYard to FemtometerYard to FermiYard to FingerYard to FootYard to FurlongYard to HandYard to HectometerYard to InchYard to KilometerYard to KiloparsecYard to KiloyardYard to LeagueYard to Light YearYard to LinkYard to MeterYard to MicroinchYard to MicrometerYard to MicronYard to MilYard to MileYard to MillimeterYard to NailYard to NanometerYard to Nautical MileYard to ParsecYard to PerchYard to PoleYard to RodYard to RopeYard to SpanYard to TwipYard to X-unit
Ell (ell) — 26 conversions
Ell to BarleycornEll to CaliberEll to CentiinchEll to CentimeterEll to ChainEll to FingerEll to FootEll to FurlongEll to HandEll to InchEll to KilometerEll to KiloyardEll to LeagueEll to LinkEll to MeterEll to MicroinchEll to MilEll to MileEll to MillimeterEll to NailEll to PerchEll to PoleEll to RodEll to RopeEll to SpanEll to Yard
Rod (rod) — 26 conversions
Rod to BarleycornRod to CaliberRod to CentiinchRod to CentimeterRod to ChainRod to EllRod to FingerRod to FootRod to FurlongRod to HandRod to InchRod to KilometerRod to KiloyardRod to LeagueRod to LinkRod to MeterRod to MicroinchRod to MilRod to MileRod to MillimeterRod to NailRod to PerchRod to PoleRod to RopeRod to SpanRod to Yard
Perch (perch) — 26 conversions
Perch to BarleycornPerch to CaliberPerch to CentiinchPerch to CentimeterPerch to ChainPerch to EllPerch to FingerPerch to FootPerch to FurlongPerch to HandPerch to InchPerch to KilometerPerch to KiloyardPerch to LeaguePerch to LinkPerch to MeterPerch to MicroinchPerch to MilPerch to MilePerch to MillimeterPerch to NailPerch to PolePerch to RodPerch to RopePerch to SpanPerch to Yard
Pole (pole) — 26 conversions
Pole to BarleycornPole to CaliberPole to CentiinchPole to CentimeterPole to ChainPole to EllPole to FingerPole to FootPole to FurlongPole to HandPole to InchPole to KilometerPole to KiloyardPole to LeaguePole to LinkPole to MeterPole to MicroinchPole to MilPole to MilePole to MillimeterPole to NailPole to PerchPole to RodPole to RopePole to SpanPole to Yard
Rope (rope) — 26 conversions
Rope to BarleycornRope to CaliberRope to CentiinchRope to CentimeterRope to ChainRope to EllRope to FingerRope to FootRope to FurlongRope to HandRope to InchRope to KilometerRope to KiloyardRope to LeagueRope to LinkRope to MeterRope to MicroinchRope to MilRope to MileRope to MillimeterRope to NailRope to PerchRope to PoleRope to RodRope to SpanRope to Yard
Chain (chain) — 26 conversions
Chain to BarleycornChain to CaliberChain to CentiinchChain to CentimeterChain to EllChain to FingerChain to FootChain to FurlongChain to HandChain to InchChain to KilometerChain to KiloyardChain to LeagueChain to LinkChain to MeterChain to MicroinchChain to MilChain to MileChain to MillimeterChain to NailChain to PerchChain to PoleChain to RodChain to RopeChain to SpanChain to Yard
Furlong (furlong) — 26 conversions
Furlong to BarleycornFurlong to CaliberFurlong to CentiinchFurlong to CentimeterFurlong to ChainFurlong to EllFurlong to FingerFurlong to FootFurlong to HandFurlong to InchFurlong to KilometerFurlong to KiloyardFurlong to LeagueFurlong to LinkFurlong to MeterFurlong to MicroinchFurlong to MilFurlong to MileFurlong to MillimeterFurlong to NailFurlong to PerchFurlong to PoleFurlong to RodFurlong to RopeFurlong to SpanFurlong to Yard
Kiloyard (kyd) — 26 conversions
Kiloyard to BarleycornKiloyard to CaliberKiloyard to CentiinchKiloyard to CentimeterKiloyard to ChainKiloyard to EllKiloyard to FingerKiloyard to FootKiloyard to FurlongKiloyard to HandKiloyard to InchKiloyard to KilometerKiloyard to LeagueKiloyard to LinkKiloyard to MeterKiloyard to MicroinchKiloyard to MilKiloyard to MileKiloyard to MillimeterKiloyard to NailKiloyard to PerchKiloyard to PoleKiloyard to RodKiloyard to RopeKiloyard to SpanKiloyard to Yard
Mile (mi) — 45 conversions
Mile to Bohr RadiusMile to Planck LengthMile to AngstromMile to AttometerMile to BarleycornMile to CaliberMile to CentiinchMile to CentimeterMile to ChainMile to DecimeterMile to DekameterMile to EllMile to FemtometerMile to FermiMile to FingerMile to FootMile to FurlongMile to HandMile to HectometerMile to InchMile to KilometerMile to KiloparsecMile to KiloyardMile to LeagueMile to Light YearMile to LinkMile to MeterMile to MicroinchMile to MicrometerMile to MicronMile to MilMile to MillimeterMile to NailMile to NanometerMile to Nautical MileMile to ParsecMile to PerchMile to PicometerMile to PoleMile to RodMile to RopeMile to SpanMile to TwipMile to X-unitMile to Yard
Nautical Mile (nmi) — 12 conversions
League (league) — 26 conversions
League to BarleycornLeague to CaliberLeague to CentiinchLeague to CentimeterLeague to ChainLeague to EllLeague to FingerLeague to FootLeague to FurlongLeague to HandLeague to InchLeague to KilometerLeague to KiloyardLeague to LinkLeague to MeterLeague to MicroinchLeague to MilLeague to MileLeague to MillimeterLeague to NailLeague to PerchLeague to PoleLeague to RodLeague to RopeLeague to SpanLeague to Yard
Astronomical
Light Year (ly) — 10 conversions
Parsec (pc) — 10 conversions
Atomic / Physics
Planck Length (planck) — 12 conversions
Fermi (fermi) — 12 conversions
X-unit (xunit) — 12 conversions
Bohr Radius (a0) — 12 conversions
Typographic
Frequently asked questions
What is the SI base unit of length?
The meter (symbol: m). Since 2019, it has been defined by fixing the speed of light in vacuum to exactly 299,792,458 m/s.
How many meters are in a mile?
1 mile = 1,609.344 meters exactly. Most calculators round this to 1,609.34 or 1,609 m.
Why does the US use feet and inches when the rest of the world uses metric?
The US adopted the British Imperial system at independence and has not officially switched, though all US measurements are now legally defined in terms of metric units (1 inch = 25.4 mm exactly).
What's the difference between a nautical mile and a regular mile?
A nautical mile (1,852 m) is defined as one minute of arc along Earth's surface, used for sea and air navigation. A statute mile (1,609.344 m) is the standard land mile.
How precise are the conversions on this site?
All factors are stored exactly per BIPM/NIST definitions. Displayed results are rounded only at the final step, so a number you see has full machine precision behind it.
Source & reference
Definitions and conversion factors on this page follow the BIPM — International System of Units and the NIST guide to the SI. Imperial-to-metric conversions use the 1959 International Yard and Pound Agreement (1 yd = 0.9144 m exactly). Historical and ancient unit values follow standard reference works in metrology and archaeology.