Length Converter
Convert length and distance between metric and imperial units — enter a value and pick the units to convert from and to.
Common length conversions
| From | To | Multiply by |
|---|---|---|
| Inches | Centimeters | 2.54 |
| Feet | Meters | 0.3048 |
| Meters | Feet | 3.281 |
| Miles | Kilometers | 1.609 |
| Kilometers | Miles | 0.6214 |
| Yards | Meters | 0.9144 |
1 inch = 2.54 cm · 1 foot = 0.3048 m · 1 meter = 3.281 ft · 1 mile = 1.609 km · 1 yard = 0.9144 m
A marathon is 42.195 km. Using 1 mile = 1.609 km: 42.195 ÷ 1.609 ≈ 26.22 miles — the standard marathon distance you'll see quoted as "26.2 miles."
Metric and imperial, side by side
Length conversions come up constantly — travel, DIY, shipping, fitness, and following instructions written for the other system. The conversions are exact by definition (an inch is defined as exactly 2.54 cm), so results are precise. For area and volume, remember the factor squares or cubes: 1 square meter is 10.76 square feet, not 3.28. For converting a running distance to a pace, see the pace calculator; for weights, the weight converter; and for temperatures, the temperature converter.
Why these factors are exact, not approximations
Unlike many unit conversions that rely on physical measurement, the inch-to-centimeter relationship (2.54 cm exactly) was fixed by international agreement in 1959, which is why every other imperial-to-metric length factor here derives cleanly from it with no rounding error. That's different from, say, a calorie-to-joule conversion, which depends on a measured physical constant — length conversions are definitional, so the numbers in the table above are exact to as many decimal places as you need.
Common length-conversion mistakes
- Squaring or cubing the wrong number when converting area or volume. Converting square meters to square feet requires squaring the linear factor (3.281² ≈ 10.76), not using 3.281 directly — using the linear factor for an area conversion understates the result by roughly a factor of 3.
- Confusing a nautical mile with a statute mile. A nautical mile (used in aviation and marine navigation) is about 1.852 km, noticeably longer than the standard statute mile (1.609 km) used for driving distances — mixing them up matters for flight-planning and boating calculations.
- Rounding intermediate steps in a multi-unit conversion chain. Converting inches to meters via feet and rounding at each step compounds small errors — keep full precision until the final result whenever a calculation has more than one step.
Frequently asked questions
How many feet are in a meter?
About 3.281 feet (39.37 inches).
How do I convert miles to kilometers?
Multiply by 1.609. 5 miles = 8.05 km.
How many centimeters in an inch?
Exactly 2.54 cm.
Are these conversion factors exact or rounded?
The inch-to-centimeter relationship (2.54 cm) is an exact international definition set in 1959, so length conversions derived from it are exact rather than measured approximations.
How do I convert an area, like square meters to square feet?
Square the linear factor: 1 m ≈ 3.281 ft, so 1 m² ≈ 3.281² ≈ 10.76 sq ft — not 3.281 directly.
Is a nautical mile the same as a regular mile?
No — a nautical mile is about 1.852 km (aviation/marine use), longer than the 1.609 km statute mile used for driving.
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Last reviewed: September 2026.