Length Converter
cm, m, in, ft, yd, mile, etc.
Complete Guide to Length Unit Conversion
Length is a physical quantity representing the distance between two points, and the metric system (SI units) and the imperial system are mixed worldwide. Accurate length conversion is essential from daily life to construction, manufacturing, international trade, navigation, and aviation. This calculator provides accurate measurements needed in various situations by converting 13 length units in real time.
Metric System (SI Units) - International Standard
The metric system is the international standard system of units used in most countries around the world. The base unit is the meter (m) and is based on a decimal system. It is used as a standard in all fields including science, engineering, medicine, and education.
- •1 Kilometer (km) = 1,000m = 0.621371 miles. Used for road distances and map measurements
- •1 Meter (m) = 100cm = 1,000mm. Base unit for construction, interior design, and sports venues
- •1 Centimeter (cm) = 10mm = 0.01m. Mainly used for body measurements, clothing sizes, and furniture
- •1 Millimeter (mm) = 0.1cm = 0.001m. Essential for precision measurement, engineering drawings, and electronic components
Imperial System - US and UK Standard
The imperial system is a measurement system mainly used in the United States, United Kingdom, and some Commonwealth countries. It is widely used especially in the United States in daily life, construction, sports, and the automotive industry.
- •1 Mile (mile) = 1,609.344m = 1.609km = 5,280 feet. US road distances, marathon course (26.2 miles)
- •1 Yard (yard, yd) = 0.9144m = 91.44cm = 3 feet. American football field (100 yards), golf distance
- •1 Foot (foot, ft) = 30.48cm = 12 inches = 0.3048m. Building height, person height, TV screen size
- •1 Inch (inch, in, ") = 2.54cm = 25.4mm. Smartphone screen size, laptop size, TV size
KRTraditional Measurement - Hanok, Hanbok, Traditional Construction
Korean traditional measurement is a unit of length used since the Joseon Dynasty and is still used in Hanok construction, Hanbok making, and traditional woodworking.
- •1 Ja (Cheok, 尺) = Approx. 30.3cm = 303mm. Base unit for Hanok spacing and traditional furniture
- •1 Chi (Chon, 寸) = 3.03cm = 1/10 Ja. Used for detailed measurements
- •1 Gan (Kan, 間) = Approx. 1.818m = 6 Ja. Distance between columns in Hanok
- •1 Jeong (Jeong, 町) = Approx. 109.09m = 60 Gan. Distance unit in traditional villages
- •1 Ri (Ri, 里) = Approx. 392.72m = Approx. 393m. Traditional distance unit, approx. 0.39km
Nautical Mile - Navigation and Aviation Only
Nautical mile (nmi) is a distance unit used in navigation and aviation, corresponding to one minute of latitude on Earth.
- •1 Nautical Mile (nmi) = Exactly 1,852m = 1.852km. Standardized as the international nautical mile
- •1 Nautical Mile = Approx. 1.151 miles. Used for measuring aircraft and ship speeds
- •1 Knot (knot) = 1 nautical mile/hour. Speed unit for ships and aircraft
Real-life Length Conversion Examples
- Marathon Course: 42.195km = 26.2 miles = Approx. 26,247 yards
- Football Field: 105m x 68m = Approx. 35 gan x 23 gan
- Swimming Pool: 50m = 54.68 yards = Approx. 27.5 gan
- Apartment Size: 84m² = Approx. 25.4 pyeong = Approx. 904ft²
- Ceiling Height: 2.4m = 240cm = Approx. 7.87ft
- Door Height: 2.1m = 210cm = Approx. 6.89ft
- Smartphone Screen: 6.1 inches = Approx. 15.5cm (diagonal)
- Laptop Screen: 15.6 inches = Approx. 39.6cm (diagonal)
- TV Screen: 55 inches = Approx. 139.7cm (diagonal) = Approx. 4.58ft
Practical Tips and Precautions for Length Conversion
Length Conversion Tip when Traveling to the US
In the United States, distance signs are in miles. 1 mile is about 1.6km, so multiply miles by 1.6 when converting to km.
Precautions when Choosing TV/Monitor Size
TV or monitor sizes are expressed in inches diagonally. 1 inch is 2.54cm.