MPH to KM/H Converter - Free Online Tool

Convert miles per hour to kilometers per hour instantly. 1 mph = 1.60934 km/h. Fast speed conversion. No signup, works offline.

Quick Reference

mph	km/h	Context
20 mph	32.2 km/h	School zone
30 mph	48.3 km/h	City street
55 mph	88.5 km/h	Rural highway
65 mph	104.6 km/h	Highway speed limit
70 mph	112.7 km/h	Interstate
80 mph	128.7 km/h	High-speed highway

Fahrenheit to Celsius Converter - Free T…

KM/H to MPH Converter - Free Online Tool

CM to Inches Converter - Metric to Imper…

Ounces to Grams Converter - Free Online …

Inches to CM Converter - Free Online Too…

View all Unit calculators →

Frequently Asked Questions

The formula is: km/h = mph × 1.60934. This is based on the fact that 1 mile equals 1.609344 kilometers. So a speed in miles per hour multiplied by 1.60934 gives the equivalent speed in kilometers per hour.

Most countries worldwide use km/h for speed limits and distance markers. When driving in Canada, Europe, Australia, or most other countries, you need to understand km/h to obey speed limits, estimate travel times, and read road signs correctly.

Miles per hour comes from the British imperial system, adopted by the US. When the metric system was developed in France (1795), it used kilometers. Most countries adopted metric during the 19th-20th centuries, while the US retained imperial units. Only the US, UK (partially), and a handful of other countries still use mph.

Quick method: multiply mph by 1.6. Even faster: multiply by 1.5 and add 10% for rough estimates. Example: 60 mph × 1.5 = 90, plus 6 (10%) = 96 km/h (actual: 96.56). For precision, use 1.609 or this converter.

Common conversions: 25 mph = 40 km/h (residential), 35 mph = 56 km/h (city), 55 mph = 89 km/h (rural), 65 mph = 105 km/h (highway), 75 mph = 121 km/h (interstate). These help interpret foreign speed limits.

For driving, rounding to the nearest whole km/h is fine. This converter provides decimal precision, useful for vehicle specs, GPS calibration, or scientific applications. Speed limit signs are always whole numbers.

Most modern vehicles have dual-scale speedometers showing both units. In the US, mph is prominent with km/h smaller. In metric countries, km/h is prominent. Some digital displays let you switch the primary unit.

Yes. All conversions are calculated in your browser using JavaScript. No speed values are sent to any server or tracked. The tool works offline and your data remains completely private.

This tool converts one speed at a time for clarity and accuracy. Simply enter a value, get the instant result, then enter another. The real-time calculation makes multiple conversions very fast.

Remember '8 to 5': 8 km ≈ 5 miles (exactly 1.609 ratio). So 80 km/h ≈ 50 mph. Or remember 60 mph ≈ 100 km/h (actually 96.5, but close). For exactness, multiply mph by 1.6.

Related Tools