Why use this calculator
Length conversion is needed for international travel, online shopping, construction, and academic work across metric and imperial systems.
How to use it
Enter a value and select the unit you're converting from. All equivalent lengths are displayed simultaneously.
The formula
All conversions go through meters as the base unit. 1 inch = 2.54 cm, 1 foot = 30.48 cm, 1 mile = 1.609 km.
Worked examples
100 cm
39.37 inches, 3.28 feet, 1 meter
When people use it
- International shopping
- Construction projects
- Academic work
- Travel planning
Tips
- 1 inch = 2.54 cm is the key conversion to remember
- 1 mile ≈ 1.6 km for quick mental math
Questions people ask
- What's the difference between metric and imperial?
- Metric (cm, m, km) is base-10 and used worldwide. Imperial (inches, feet, miles) is used primarily in the US, UK (partially), and a few other countries.