Length Converter - cm to inches, meters to feet, km to miles
Convert between millimeters, centimeters, meters, kilometers, inches, feet, yards, and miles instantly.
How to Use the Length Converter
- Choose Source Unit: Select the length unit you're converting from (e.g., centimeters, meters, inches, feet) from the "From" dropdown.
- Input Length Value: Enter the length measurement you want to convert. You can use whole numbers or decimals for precise measurements.
- Select Target Unit: Choose the unit you want to convert to from the "To" dropdown menu.
- Get Instant Conversion: Your converted length appears immediately. Use the copy button to save it or add to favorites for quick access later.
Length Conversion Formulas
Centimeters to Inches
inches = cm ÷ 2.54Example: 10 cm = 10 ÷ 2.54 = 3.937 inches
Meters to Feet
feet = meters × 3.28084Example: 2 meters = 2 × 3.28084 = 6.562 feet
Kilometers to Miles
miles = kilometers × 0.621371Example: 10 km = 10 × 0.621371 = 6.214 miles
Length Conversion Reference Table
| Metric | Imperial | Conversion Factor | Common Use |
|---|---|---|---|
| 1 mm | 0.039 inches | × 0.039 | Precision measurements |
| 1 cm | 0.394 inches | × 0.394 | Everyday measurements |
| 1 m | 3.281 feet | × 3.281 | Room dimensions |
| 1 km | 0.621 miles | × 0.621 | Travel distance |
| 1 inch | 2.54 cm | × 2.54 | Screen sizes, height |
| 1 foot | 30.48 cm | × 30.48 | Height, room size |
| 1 mile | 1.609 km | × 1.609 | Road distances |
Real-World Length Conversion Examples
Height Conversion
Convert human height between centimeters (used globally) and feet/inches (used in US/UK). For example, 180 cm equals 5 feet 11 inches, which is considered tall in most countries.
Travel Distance
Convert road distances between kilometers (used worldwide) and miles (used in US/UK). A 100 km trip equals approximately 62 miles, helping you plan travel time and fuel consumption.
Construction Measurements
Convert building dimensions between metric (meters) and imperial (feet). Essential for international construction projects, architectural plans, and material ordering.
Fabric & Textiles
Convert fabric lengths between centimeters and inches. Useful for sewing patterns, textile measurements, and understanding international sizing charts for clothing.
Understanding Length Measurement Systems
Metric vs Imperial Systems
The metric system (meters, centimeters) is used by most countries worldwide and is based on powers of 10, making calculations easier. The imperial system (feet, inches, miles) is primarily used in the United States and a few other countries. Metric units are generally easier to work with mathematically because conversions involve simple multiplication or division by 10, 100, or 1000.
Why Different Units?
Different units developed historically in different regions. The metric system was created during the French Revolution for standardization, while imperial units evolved from ancient Roman and British measurements. Most countries have adopted metric for its simplicity, but the US still primarily uses imperial units due to tradition and the cost of conversion.
Choosing the Right Unit
Use millimeters for very small measurements (jewelry, electronics), centimeters for everyday items (height, clothing), meters for rooms and buildings, and kilometers for distances. Imperial units follow similar logic with inches, feet, and miles. Always use the unit that makes the most sense for your specific application.
Length Conversion Tips
- 1 inch = exactly 2.54 cm (this is the official conversion factor used worldwide)
- For quick height conversion: 1 foot = 30 cm (approximately, exact is 30.48 cm)
- 1 mile is slightly longer than 1.6 kilometers (exact: 1.60934 km)
- When measuring fabric, remember 1 yard = 0.9144 meters = 36 inches
- For construction, always double-check conversions as small errors can compound in large projects