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Length Converter

Convert any length measurement between metric, imperial, and many more units. Toggle Advanced Mode for dozens of extras.

Enter Length to Convert

Show dozens of extra length units (e.g., rod, chain, fathom, nautical mile, light‐year, parsec, etc.).

Conversion Result

Converted Value: -

Overview

A length converter is an essential tool for anyone dealing with measurements—whether you’re a student completing homework, a professional working on blueprints, or a homeowner planning a project. This free online tool converts between basic metric units (mm, cm, m, km), imperial units (in, ft, yd, mi), and, in Advanced Mode, dozens of additional units (micrometer, nanometer, decimeter, fathom, rod, chain, link, league, nautical mile, Ångström, light‐year, parsec, astronomical unit, typographic points/picas, hands, nautical feet, cables, etc.).

Simply toggle “Advanced Mode” to reveal the extended list. Then select your source unit, target unit, enter the numeric value, and click “Convert” to see the precise result. No registration is required, and it works on desktop and mobile devices.

Formula & Methodology

Conversions are performed using standardized factors relative to one meter. Internally, all input values are converted to meters, then from meters to the chosen target unit. For example, to convert 10 inches to centimeters:

1. Convert 10 inches → meters: $$10\ \text{in} \times 0.0254 \frac{\text{m}}{\text{in}} = 0.254\ \text{m}.$$ 2. Convert 0.254 meters → centimeters: $$0.254\ \text{m} \times 100 \frac{\text{cm}}{\text{m}} = 25.4\ \text{cm}.$$

All unit‐to‐meter factors used here are taken from authoritative sources (NIST, BIPM, etc.). Once in meters, converting to any other unit only requires dividing by that unit’s meter factor.

Examples of a few conversion constants:
• 1 inch = 0.0254 m
• 1 foot = 0.3048 m
• 1 yard = 0.9144 m
• 1 mile = 1609.344 m
• 1 rod = 5.0292 m
• 1 nautical mile = 1852 m
• 1 light‐year = 9.4607×1015 m
• 1 parsec = 3.0857×1016 m

Examples

  • Convert 10 inches to centimeters:
    $$10\ \text{in} \times 2.54 = 25.4\ \text{cm}.$$
  • Convert 5 miles to kilometers:
    $$5\ \text{mi} \times 1.60934 = 8.0467\ \text{km}.$$
  • Convert 100 centimeters to feet:
    $$100\ \text{cm} \times 0.0328084 = 3.28084\ \text{ft}.$$
  • Convert 2 rods to yards:
    1 rod = 5.0292 m; 1 yard = 0.9144 m, so 2 rods = 10.0584 m → 10.0584 ÷ 0.9144 = 11.0 yd.
  • Convert 1 light-year to kilometers:
    1 ly = 9.4607×1015 m; in km = 9.4607×1012 km.

Frequently Asked Questions

What units can I convert?

This converter supports: **Basic**: millimeters, centimeters, meters, kilometers, inches, feet, yards, miles. **Advanced**: micrometers (μm), nanometers (nm), decimeters (dm), fathoms, rods, chains, links, leagues, nautical miles, Ångströms (Å), light‐years (ly), parsecs (pc), astronomical units (AU), typographic points & picas (pt/pc), hands (hh), nautical feet, cables (cbl), etc.

How precise are the results?

Results use exact, internationally recognized constants (e.g., 1 in = 2.54 cm exactly). The output is displayed to six decimal places by default. You may round as needed.

Why would I need Advanced Mode?

Advanced Mode reveals less‐common and historical units (e.g., rods, chains, cables, fathoms, nautical miles, light‐years, parsecs). It’s useful for specialized projects in surveying, navigation, astronomy, or historical research.

Is this converter free to use?

Yes—Length Converter is completely free and does not require registration.

Can I use this on my phone or tablet?

Absolutely. The page is fully responsive and adapts to any screen size. Just open it in your browser and use it directly.