Length Converter

Convert between millimeters, centimeters, meters, kilometers, inches, feet, yards, miles, and more instantly.

Value

From

Common Length Conversions

From	To	Multiply by
Meter	Foot	3.28084
Meter	Inch	39.3701
Kilometer	Mile	0.621371
Mile	Kilometer	1.60934
Foot	Centimeter	30.48
Inch	Centimeter	2.54
Yard	Meter	0.9144
Nautical Mile	Kilometer	1.852

Frequently Asked Questions

One meter equals exactly 3.28084 feet (or 3 feet and 3.37 inches). The meter is the SI base unit of length. One foot is defined as exactly 0.3048 meters.

One mile equals 1.60934 kilometers. Conversely, one kilometer equals approximately 0.621371 miles. The mile is used primarily in the United States and United Kingdom for road distances.

A nautical mile is 1,852 meters (1.852 km). It is based on the circumference of the Earth and equals one minute of arc of latitude. It is used in aviation and maritime navigation worldwide.

There are exactly 12 inches in a foot. One inch equals 2.54 centimeters exactly (defined since 1959). One foot therefore equals 30.48 centimeters.

The most common conversions are miles to kilometers (1 mile = 1.60934 km), feet to meters (1 ft = 0.3048 m), and inches to centimeters (1 in = 2.54 cm). These come up constantly in travel, construction, and sports contexts where countries use different systems.

The metric system was developed in France in the 1790s and adopted internationally for its logical base-10 structure. The United States, Myanmar, and Liberia are the only countries that have not officially adopted the metric system as primary, largely due to the cost of conversion and entrenched cultural habits. The UK uses a mix of both.

Multiply the number of miles by 1.60934 to get kilometers. For a quick mental estimate, multiply by 1.6 (slightly under). For example, 5 miles × 1.6 = 8 km (exact: 8.047 km). To go the other way, multiply kilometers by 0.621 to get miles.

A nautical mile equals 1,852 meters (1.852 km), while a statute (land) mile is 1,609.34 meters. The nautical mile is based on Earth's geometry — one nautical mile corresponds to one minute of arc of latitude. It is the standard unit in aviation and maritime navigation worldwide.

One light-year is approximately 9.461 × 10¹² km (about 9.46 trillion kilometers). It is the distance light travels in one Julian year at 299,792,458 m/s. Light-years are used in astronomy to express stellar distances — the nearest star, Proxima Centauri, is about 4.24 light-years away.

An angstrom (Å) is 10⁻¹⁰ meters (0.1 nanometers). It is used in physics and chemistry to describe atomic and molecular scales — for example, a hydrogen atom has a radius of about 0.53 Å, and visible light wavelengths range from about 3,800 to 7,000 Å.

About This Length Converter

This free length converter converts between metres, kilometres, centimetres, millimetres, miles, yards, feet, inches, nautical miles, and other length units. Enter a value in any field and all others update instantly.

When to use this converter

Converting distances for travel, maps, and navigation
Converting body measurements between metric and imperial
Translating engineering drawings between unit systems

Standards & References

How It Works

Enter a Value

Type any number in the value field. Decimals and very large or small numbers are supported.

Select Units

Choose the source and target units from the dropdowns. Use Swap to reverse the direction instantly.

Get Instant Result

The result updates in real-time as you type. All conversions use precise, industry-standard factors.

Common Use Cases

Home Improvement

Convert room dimensions between metric and imperial when working with international floor plans, furniture specs, or building materials.

Travel & Navigation

Convert road distances from miles to kilometers when traveling between countries that use different measurement systems.

Education & Science

Convert between SI and imperial units for physics, engineering, and science homework or lab reports.

E-commerce

Convert product dimensions when listing items for international markets or comparing measurements from overseas suppliers.

Aviation & Maritime

Convert altitudes, distances, and runway lengths between feet, meters, and nautical miles as used in aviation and maritime contexts.

Sports & Fitness

Convert race distances (5K, 10K, marathon) between kilometers and miles for training plans and event registrations.

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