Length Converter

How to use it

The base unit for length is the meter, and every other unit here is defined as an exact multiple of it. A millimeter is a thousandth of a meter, a kilometer is a thousand meters, and the imperial units are pinned to the meter by international agreement rather than by any physical object — an inch has been defined as exactly 2.54 centimeters since 1959, a foot is exactly 0.3048 meters (12 inches), a yard is exactly 0.9144 meters (3 feet), and a mile is exactly 1609.344 meters (5,280 feet). To convert, this tool multiplies your value by the source unit's factor to get meters, then divides by the target unit's factor. Converting 10 feet to meters: 10 × 0.3048 = 3.048 m. Converting 5 kilometers to miles: 5000 m ÷ 1609.344 ≈ 3.107 mi. Because the inch-to-centimeter relationship is exact, there's no rounding error hiding in any length conversion — the results you see are as precise as the decimal places shown. Length is the category where the metric and imperial systems mix the most in everyday life: a recipe might call for centimeters, a hardware store sells lumber in feet and inches, and a road sign in the US shows miles while one in Europe shows kilometers. A quick reference: 1 inch ≈ 2.54 cm, 1 foot ≈ 30.48 cm, 1 yard ≈ 0.91 m, and 1 mile ≈ 1.61 km. Doubling a metric value and knocking a bit off is a rough way to eyeball miles-to-km, but for anything that needs to be right — a shipping label, a construction measurement, a pace calculation — use the exact conversion above rather than the mental shortcut.

Frequently asked questions

How many centimeters are in an inch?

Exactly 2.54 centimeters — this has been the internationally agreed definition since 1959, so it's not a rounded approximation. That makes it the most reliable anchor point for converting between metric and imperial length units; every other inch-based conversion (feet, yards, miles) derives from this fixed ratio.

Why is a mile such an odd number of meters (1609.344)?

A mile is defined as 5,280 feet, and a foot is exactly 0.3048 meters, so multiplying those out gives 1609.344 meters exactly. It looks awkward in metric because the mile was standardized from old British units, not designed around the meter.

What's the difference between a nautical mile and a regular mile?

A nautical mile (1,852 meters) is based on one minute of latitude on Earth's surface and is used for sea and air navigation. A regular (statute) mile is 1,609.344 meters and is used for road distances. They're about 15% apart, so don't mix them up when reading a chart.

Why do my feet-to-meters conversions sometimes look rounded differently elsewhere?

Some sites round intermediate steps (like rounding 0.3048 to 0.305) before finishing the calculation, which introduces small errors that compound over larger numbers. This tool keeps full floating-point precision through the entire calculation and only rounds the final displayed result, so it stays accurate even for large values.