Length Converter
Instantly convert between all units of length and distance — meters, feet, inches, kilometers, miles, yards, and more. Free online length converter for everyday and scientific use.
Understanding Length Measurements
Length measures distance between two points. The metric system uses meters as the base unit, while the imperial system uses feet and inches. You encounter length measurements daily when measuring rooms, checking your height, or planning travel distances.
The International System of Units (SI) defines the meter as the standard unit of length. One meter equals the distance light travels in vacuum during 1/299,792,458 of a second. This definition ensures precise, consistent measurements worldwide.
Length Conversion Formulas
Meters to Feet
feet = meters × 3.28084
Example: 5 m × 3.28084 = 16.404 ft
Feet to Meters
meters = feet × 0.3048
Example: 10 ft × 0.3048 = 3.048 m
Kilometers to Miles
miles = kilometers × 0.621371
Example: 100 km × 0.621371 = 62.137 mi
Inches to Centimeters
cm = inches × 2.54
Example: 12 in × 2.54 = 30.48 cm
Common Length Conversions
| Metric | Imperial Equivalent |
|---|---|
| 1 millimeter | 0.039 inches |
| 1 centimeter | 0.394 inches |
| 1 meter | 3.281 feet |
| 1 kilometer | 0.621 miles |
| 10 meters | 32.808 feet |
| 100 meters | 328.084 feet |
Length Unit Reference Table
| Unit | Symbol | Equals 1 Unit In Meters | System |
|---|---|---|---|
| Millimeter | mm | 0.001 m | Metric |
| Centimeter | cm | 0.01 m | Metric |
| Meter | m | 1 m | Metric (SI) |
| Kilometer | km | 1,000 m | Metric |
| Inch | in | 0.0254 m | Imperial |
| Foot | ft | 0.3048 m | Imperial |
| Yard | yd | 0.9144 m | Imperial |
| Mile | mi | 1,609.344 m | Imperial |
| Nautical Mile | nmi | 1,852 m | Navigation |
Real-World Length Examples
| Object/Distance | Measurement |
|---|---|
| Standard door height | 2.0 meters (6.56 feet) |
| Olympic swimming pool | 50 meters (164.04 feet) |
| Football field (NFL) | 109.7 meters (120 yards) |
| Basketball court (NBA) | 28.65 meters (94 feet) |
| Marathon race | 42.195 kilometers (26.22 miles) |
| Average human height (male) | 1.75 meters (5.74 feet) |
When to Use Each Length Unit
Millimeters (mm)
Precision engineering, manufacturing tolerances, small mechanical parts
Centimeters (cm)
Body measurements, clothing sizes, small household objects
Meters (m)
Room dimensions, human height, sports distances, construction
Kilometers (km)
Road distances, running events, geography, travel planning
Inches (in)
Screen sizes, pipe diameters, lumber thickness, small measurements
Feet (ft)
Room dimensions, human height (US/UK), building heights
Yards (yd)
Fabric lengths, sports fields (American football), landscaping
Miles (mi)
Road distances (US/UK), running events, geography
Frequently Asked Questions
How do I convert meters to feet quickly?
Multiply meters by 3.28 for a quick estimate. For precise conversions, use 3.28084. Example: 2 meters × 3.28 = 6.56 feet.
What is the difference between a nautical mile and a regular mile?
A nautical mile equals 1,852 meters (6,076 feet), while a statute mile equals 1,609 meters (5,280 feet). Nautical miles measure distance at sea and in aviation, based on Earth's circumference.
Why does the US still use inches and feet?
The US customary system evolved from British imperial units. Despite global metric adoption, the US maintains imperial units due to existing infrastructure, manufacturing standards, and public familiarity.
How accurate is the inch to centimeter conversion?
The conversion is exact: 1 inch equals precisely 2.54 centimeters. This definition was internationally agreed upon in 1959, ensuring consistent conversions worldwide.
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