km/h ↔ mph Converter
Instantly convert speed between kilometers per hour and miles per hour. Perfect for travel and speed limit conversion.
Result
- Kilometers per Hour
- 0
- Miles per Hour
- 0
Formula & Guide
Conversion Formulas
K
km/h to mph
mph = km/h × 0.621371
Multiply by 0.621371 to convert km/h to mph
M
mph to km/h
km/h = mph × 1.60934
Multiply by 1.60934 to convert mph to km/h
Step-by-Step Scenario
Example Scenario
Speed
100 km/h
Target Unit
mph
1
Apply Conversion Formula
- mph = km/h × 0.621371
2
Calculate
- mph = 100 × 0.621371
Additional Examples
Highway Speed
Input: 120 km/h
Result
120 × 0.621371 = 74.56 mph
City Speed
Input: 50 mph
Result
50 × 1.60934 = 80.47 km/h
Characteristics of Speed Conversion
Precise Factor
Uses exact conversion factor: 1 mph = 1.609344 km/h. Ensures accurate speed conversions.
Travel Essential
Perfect for international travel, speed limit conversion, and understanding vehicle speeds in different countries.
Real-Time Conversion
Instant conversion as you type. Both directions are calculated simultaneously.
Bidirectional
Convert from km/h to mph or mph to km/h with equal accuracy and precision.
Important Notes
- The conversion factor is based on 1 mile = 1.609344 kilometers. This is the exact relationship between miles and kilometers.
- For practical use, round results to 1-2 decimal places. The calculator shows up to 4 decimals for precision.
- Most countries use km/h (metric system). The United States uses mph (imperial system).
- When traveling internationally, speed limits are often in km/h. This calculator helps convert to mph for US drivers.
- For vehicle speedometers, many cars show both km/h and mph. This calculator helps verify conversions.
Frequently Asked Questions
Find answers to common questions about speed conversion.