Convert between meters, feet, inches, miles, kilometers, centimeters, yards, and nautical miles instantly. Accurate metric and imperial length conversions for everyday use.
The most commonly needed metric-to-imperial conversions
Enter a value in any unit and get instant conversions to all other length units — metric, imperial, and nautical.
Open Unit Converter →Our length converter handles all major units across three systems:
Metric system: millimeters (mm), centimeters (cm), meters (m), kilometers (km)
Imperial/US customary: inches (in), feet (ft), yards (yd), miles (mi)
Nautical: nautical miles (nmi)
All conversions chain through meters as the base SI unit. The fundamental conversion anchor is that 1 inch = 2.54 cm exactly — this is a defined, exact value, not an approximation, established by international agreement in 1959.
The metric system, used by 95% of the world's population, is built on powers of ten. Each unit is exactly 10× the previous: 1 meter = 100 cm = 1,000 mm = 0.001 km. This makes arithmetic between units simple — just move the decimal point.
The imperial system, dominant in the US, uses irregular relationships: 1 foot = 12 inches; 1 yard = 3 feet; 1 mile = 5,280 feet. These values come from historical standards (the foot was literally based on the length of a foot) and are less mathematically convenient but deeply embedded in US infrastructure, signage, and culture.
The US is one of only three countries (alongside Myanmar and Liberia) that hasn't officially adopted the metric system for everyday use. The Metric Conversion Act of 1975 made metric the preferred US system for trade and commerce, but everyday usage remained imperial due to enormous switching costs: replacing road signs, retooling manufacturing equipment, retraining workers, and changing consumer expectations.
Interestingly, the US uses metric in science, medicine, military, and international trade. Your soda comes in 2-liter bottles, your medicine is in milligrams, and your car's engine is measured in liters — even in the US. But road distances are in miles and heights are in feet.
5'0" = 152.4 cm | 5'6" = 167.6 cm | 5'10" = 177.8 cm | 6'0" = 182.9 cm | 6'2" = 187.9 cm
1 mile = 1.609 km | 5K = 3.107 mi | 10K = 6.214 mi | Half marathon = 13.1 mi = 21.1 km | Marathon = 26.22 mi = 42.195 km
1 yard = 0.914 m | 1 meter = 1.094 yards | 100 meters = 328 feet | 1 km = 3,281 feet
1 nautical mile = 1.852 km = 1.151 miles. Nautical miles are used in aviation and maritime navigation because they relate directly to latitude degrees (1 nautical mile ≈ 1 arcminute of latitude).
Feet to meters: meters = feet × 0.3048
Meters to feet: feet = meters × 3.28084
Inches to cm: cm = inches × 2.54
Cm to inches: inches = cm ÷ 2.54
Miles to km: km = miles × 1.60934
Km to miles: miles = km × 0.62137
Yards to meters: meters = yards × 0.9144
Nautical miles to km: km = nautical miles × 1.852
1 meter = 3.28084 feet. To convert: feet = meters × 3.281. A 6-foot person is 1.829 meters tall. To go from feet to meters: meters = feet × 0.3048.
1 inch = 2.54 cm (exactly, by definition). Multiply inches by 2.54 to get cm. Divide cm by 2.54 to get inches. 12 inches = 30.48 cm. 100 cm = 39.37 inches.
1 mile = 1.60934 km. Multiply miles by 1.609 for km. Multiply km by 0.6214 for miles. A 5K race is 3.107 miles. A marathon (26.2 mi) is 42.195 km.
Historical and cultural inertia. The US inherited British Imperial units and the enormous cost of switching (road signs, manufacturing, education) prevented adoption. Science, medicine, and international trade in the US use metric units; everyday life uses imperial.