Length Unit Converter

Top, fast, best-in-class, and free convert any length unit instantly. 100% client-side, unlimited use, and your information is 100% confidential and secure.

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Fast, Free, Private Length Unit Converter (Offline)

Convert length units instantly m, cm, mm, km, in, ft, yd, mi, µm, nm, and nautical miles (nmi). 100% client side, lifetime free, unlimited use. No uploads, no sign ups, truly private.

Built for speed and accuracy. Top, fast, best-in-class, and unlimited. Your information is 100% confidential and secure.

Why people love this length converter

Offline & secure

Runs entirely in your browser. Your values never leave your device.

Unlimited & free forever

No accounts, no limits convert as much as you want.

Fast & simple

Pick units, type a value, get results instantly with clear precision.

Works everywhere

Modern browsers on Windows, Mac, Linux, and mobile devices.

No data collected

100% client-side processing keeps your data private.

Accurate results

Reliable conversion factors with smart rounding for readability.

Popular uses worldwide

Construction & DIY

Convert inches and feet to metric for plans, cuts, and on-site measurements.

Manufacturing & machining

Switch between mm, µm, and inches for tolerances and specs.

Travel, sports & maps

Convert km and miles for routes, running, cycling, and navigation.

Interior & furniture

Plan furniture and room sizes with cm, in, ft, and m.

E commerce & product specs

Show measurements in customer friendly units for global buyers.

Education

Learn metric vs imperial with quick, visual conversions.

How to convert length units

  1. Select your “From” unit (e.g., feet).
  2. Enter a value (e.g., 2.5).
  3. Select your “To” unit (e.g., meters).
  4. See instant results and the 1 unit summary below.
  5. Use “Reset” to start again.

Tip: Change either side both fields update intelligently.

Supported units

Metre (m)
Kilometre (km)
Centimetre (cm)
Millimetre (mm)
Micrometre (µm)
Nanometre (nm)
Inch (in)
Foot (ft)
Yard (yd)
Mile (mi)
Nautical mile (nmi)

Best practices

  • Confirm metric vs imperial before sharing measurements.
  • Use the 1 unit summary to double check scaling (e.g., 1 ft = 12 in).
  • Round only at the end if you’ll do further calculations.
  • Keep original values for auditing and records.
  • Know context: mile vs nautical mile differ (land vs marine/aviation).

Frequently Asked Questions

Is it private and secure?

Yes. Everything runs locally in your browser no uploads, no tracking, no servers.

Is it really free and unlimited?

Yes. Lifetime free, unlimited conversions, and no sign ups.

Which units are supported?

m, cm, mm, km, in, ft, yd, mi, µm, nm, and nmi.

Does it work offline?

Yes. Your browser can cache assets after the first visit and run offline.

How accurate are results?

We use precise conversion constants with smart rounding for readability.

Can I use it on mobile?

Absolutely. It works on modern mobile and desktop browsers.

Global availability (GEO)

Built for users worldwide: USA, UK, Canada, Australia, India, EU (Germany, France, Spain, Italy, Netherlands), Middle East (UAE, Saudi Arabia), Asia (Singapore, Malaysia, Philippines, Indonesia, Japan, South Korea), Africa (Nigeria, South Africa, Egypt), and Latin America (Brazil, Mexico, Argentina).

Also searched as: length converter, distance converter, measurement converter, meters to feet, feet to meters, inches to centimeters, centimeters to inches, millimeters to inches, km to miles, miles to km, yards to meters, metric to imperial, imperial to metric, convert in to cm, convert ft to m, convert mm to in, convert km to mi.
Multilingual: convertidor de longitud (ES), convertisseur de longueur (FR), Längenrechner / Längeneinheiten umrechnen (DE), convertitore di lunghezza (IT), conversor de comprimento (PT), конвертер длины (RU), 長さ単位換算 (JA), 长度换算 (ZH), 길이 변환기 (KO), uzunluk dönüştürücü (TR), przelicznik długości (PL), lengte omrekenen (NL), chuyển đổi độ dài (VI), konverter panjang (ID), ตัวแปลงความยาว (TH), محول الطول (AR), लंबाई कनवर्टर (HI).

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