MulticalcLength/Distance Unit Converter
Convert between length and distance units instantlyEnter a length value to see conversions.
Length Conversion Guide
Understanding Length Units
Length is the measurement of distance between two points. Different measurement systems use different base units.
Metric System (SI):
- Millimeter (mm): 1/1000 of a meter - Small measurements
- Centimeter (cm): 1/100 of a meter - Common for everyday items
- Meter (m): Base SI unit - Human height, room dimensions
- Kilometer (km): 1000 meters - Long distances, roads
Imperial System:
- Inch (in): 1/12 of a foot - Small measurements
- Foot (ft): 12 inches - Human height, room dimensions
- Yard (yd): 3 feet - Fabric, sports fields
- Mile (mi): 5,280 feet - Long distances, roads
Quick Reference:
- 1 inch = 2.54 cm (exactly)
- 1 foot = 30.48 cm = 0.3048 m
- 1 meter ≈ 3.28 feet ≈ 39.37 inches
- 1 mile = 1.609 km
- 1 km ≈ 0.621 miles
- 1 nautical mile = 1.852 km
Common Applications
- Construction: Meters, feet, inches for building dimensions
- Sports: Meters for track, yards for football
- Navigation: Nautical miles for sea/air travel
- Manufacturing: Millimeters for precision parts
- Travel: Kilometers or miles for road distances
Pro Tips
-
Easy
Conversion
1 inch = 2.54 cm exactly. Multiply inches by 2.54 for centimeters. -
Metric Advantage
Metric system uses base-10, making conversions simple (×10, ×100, ×1000). -
Precision
For precision work, use millimeters or inches with decimal places.
Human Scale
- Average height: 170 cm (5'7")
- Arm span ≈ Height
- Foot length ≈ 15% of height
- Pace (step) ≈ 0.75 m (2.5 ft)
Frequently Asked Questions
A: 1 meter = 3.28084 feet (approximately 3.28 feet). Conversely, 1 foot = 0.3048 meters (exactly). This is one of the most common conversions between metric and imperial systems.
A: In 1959, English-speaking countries agreed to define the inch as exactly 2.54 centimeters to standardize international trade and engineering. Before this, there were slight variations in the inch definition.
A: A statute mile (regular mile) is 5,280 feet or 1.609 km. A nautical mile is 6,076 feet or 1.852 km (exactly). Nautical miles are used in aviation and maritime navigation because they're based on Earth's circumference (1 minute of latitude).
A: Quick approximations: 1 meter ≈ 3 feet, 1 km ≈ 0.6 miles, 1 inch ≈ 2.5 cm. For exact conversions, use: 1 inch = 2.54 cm, 1 mile = 1.609 km. Our calculator provides precise conversions instantly.
A: The US officially adopted the metric system in 1975 but allowed voluntary conversion. Due to the high cost of changing infrastructure, signage, and industry standards, the US continues to use imperial units for everyday measurements while using metric in science and medicine.
A: Our conversions use exact, internationally-defined conversion factors (e.g., 1 inch = 2.54 cm exactly, 1 foot = 0.3048 m exactly). Results are rounded to 8 decimal places for display, which is more than sufficient for virtually all practical applications.
Disclaimer
Important Notice:
- This converter provides accurate conversions based on internationally-defined conversion factors (e.g., 1 inch = 2.54 cm exactly).
- Conversions are rounded to 8 decimal places for display. For scientific or precision applications requiring more decimal places, use specialized tools.
- For construction and engineering, always verify measurements with calibrated tools and follow industry standards and building codes.
- Historical measurements (ancient cubits, leagues, etc.) are not included as they varied by region and time period.
- This tool converts linear measurements only. For area (square units) or volume (cubic units), use our dedicated calculators.
- Measurement accuracy depends on the precision of your input. Always use properly calibrated measuring instruments for critical applications.
- For legal, commercial, or safety-critical applications, verify conversions with certified instruments and consult relevant standards.
- Some industries use specialized units (e.g., survey feet, which differ slightly from international feet). Verify which standard applies to your application.
- We are not responsible for any errors, measurement mistakes, construction errors, or other consequences resulting from the use of this converter.
Always verify conversions for critical applications and use properly calibrated measuring equipment.
Length Converter
Convert between 9 common length and distance units instantly. Perfect for construction, travel, sports, and everyday measurements!
Supported Units
- ✓ Millimeter (mm)
- ✓ Centimeter (cm)
- ✓ Meter (m)
- ✓ Kilometer (km)
- ✓ Inch (in)
- ✓ Foot (ft)
- ✓ Yard (yd)
- ✓ Mile (mi)
- ✓ Nautical Mile (nmi)
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Did You Know?
The meter was originally defined as 1/10,000,000 of the distance from the equator to the North Pole. Today, it's defined by the speed of light: the distance light travels in 1/299,792,458 of a second!