Converter
Length & Distance

Length & Distance Converters

Instantly convert between metric and imperial length units. Every conversion uses exact constants defined by international standards — no rounding errors.

Human Height Converter

Convert feet/inches ↔ centimeters

Metric Conversions

Millimeters → Centimeters

1 mm = 0.1 cm

Centimeters → Millimeters

1 cm = 10 mm

Centimeters → Meters

1 cm = 0.01 m

Meters → Centimeters

1 m = 100 cm

Meters → Kilometers

1 m = 0.001 km

Kilometers → Meters

1 km = 1,000 m

Imperial ↔ Metric

Inches → Centimeters

1 in = 2.54 cm (exact)

Centimeters → Inches

1 cm ≈ 0.3937 in

Feet → Meters

1 ft = 0.3048 m (exact)

Meters → Feet

1 m ≈ 3.2808 ft

Yards → Meters

1 yd = 0.9144 m (exact)

Meters → Yards

1 m ≈ 1.0936 yd

Distance Conversions

Miles → Kilometers

1 mi = 1.609344 km (exact)

Kilometers → Miles

1 km ≈ 0.6214 mi

Nautical Miles → Kilometers

1 nmi = 1.852 km (exact)

Kilometers → Nautical Miles

1 km ≈ 0.5400 nmi

Frequently Asked Questions

What is the metric system for length?

The metric system uses millimeters, centimeters, meters, and kilometers. Each unit differs by a factor of 10 or 1,000, making conversions straightforward.

What is the imperial system for length?

The imperial system uses inches, feet, yards, and miles. 12 inches = 1 foot, 3 feet = 1 yard, 1,760 yards = 1 mile.

How do I convert between metric and imperial?

Use fixed conversion constants: 1 inch = 2.54 cm, 1 foot = 0.3048 m, 1 mile = 1.609344 km. Multiply or divide accordingly.

What is the base unit of length in SI?

The meter is the SI base unit of length. It was originally defined as one ten-millionth of the distance from the equator to the North Pole.

What is a nautical mile?

A nautical mile equals 1,852 meters and corresponds to one minute of latitude. It is used in maritime and air navigation.

Which length unit should I use?

Use the unit standard in your context: meters/cm for science and most countries, feet/inches in the US for everyday use, nautical miles for sea/air navigation.