Length Converter
Convert between inches, feet, yards, miles, millimeters, centimeters, meters, and kilometers. Includes common conversion tables and real-world reference examples.
Formulas, assumptions, and rounding are documented in our calculator methodology.
Enter a value in any field — all other fields update instantly.
All values use internationally accepted conversion factors.
Length Conversion Formulas
Inches ↔ cm: multiply inches × 2.54 to get cm; divide cm ÷ 2.54 to get inches. Feet ↔ meters: multiply feet × 0.3048 to get meters; divide meters ÷ 0.3048 to get feet. Miles ↔ km: multiply miles × 1.60934 to get km; multiply km × 0.621371 to get miles. Yards ↔ meters: multiply yards × 0.9144 to get meters.
Popular Length Conversions Quick Table
1 in = 2.54 cm | 6 in = 15.24 cm | 12 in = 30.48 cm (1 ft). 1 ft = 30.48 cm | 3 ft = 91.44 cm (1 yd) | 6 ft = 182.88 cm. 1 m = 3.281 ft | 1 m = 39.37 in | 1 m = 100 cm. 1 km = 0.6214 mi | 5 km = 3.107 mi | 10 km = 6.214 mi | 26.2 mi = 42.195 km (marathon).
Length Units Explained
The metric system uses millimeters (mm), centimeters (cm), meters (m), and kilometers (km). The US customary system uses inches (in), feet (ft), yards (yd), and miles (mi). 1 foot = 12 inches. 1 yard = 3 feet. 1 mile = 5,280 feet. Scientific work also uses nanometers (nm = 10⁻⁹ m) and micrometers (μm = 10⁻⁶ m).
Real-World Length Reference Examples
A standard door is about 80 in (203 cm) tall. A queen bed is 60 in wide (152 cm). A US football field is 100 yards (91.44 m) plus two 10-yard end zones. An average person's height is 5 ft 7 in (170 cm). The Empire State Building is 1,454 ft (443 m) tall. The distance from New York to Los Angeles is about 2,800 miles (4,500 km).
Frequently Asked Questions
- There are exactly 2.54 centimeters in one inch. This is the internationally defined exact value — 1 in = 2.54 cm. To convert inches to cm, multiply by 2.54. To convert cm to inches, divide by 2.54 (or multiply by 0.3937).
- One meter equals approximately 3.28084 feet (or 3 feet 3.37 inches). One foot equals exactly 0.3048 meters.
- One mile equals approximately 1.60934 kilometers. One kilometer equals approximately 0.621371 miles. A quick mental shortcut: multiply km by 0.6 to get a rough miles estimate (e.g., 100 km ≈ 62 miles).
- First convert feet to inches (multiply feet by 12), then add the remaining inches, then multiply by 2.54. Example: 5 ft 9 in = (5 × 12 + 9) = 69 inches × 2.54 = 175.26 cm.
- Length typically refers to the size of an object, while distance refers to the space between two points. Both use the same units and the same converter.