Convert mph to km/h

Convert miles per hour to kilometers per hour with the 1.60934 factor. Covers vehicle speed limits, wind speeds, sports, and aviation speed references.

Speed

Detailed Explanation

Miles per Hour to Kilometers per Hour

The formula is:

km/h = mph × 1.60934

Speed Limit Conversions

mph km/h Typical Use
15 24.1 School zone
25 40.2 Residential
35 56.3 Urban road
45 72.4 Suburban road
55 88.5 Rural highway
65 104.6 Interstate
70 112.7 Highway
75 120.7 High-speed highway
85 136.8 Texas fastest limit

Wind Speed Scales

Weather reports use different speed units by region:

Beaufort Scale highlights:

Description mph km/h
Calm <1 <1.6
Light breeze 4–7 6.4–11.3
Moderate breeze 13–18 20.9–29
Strong wind 25–31 40.2–49.9
Gale 39–46 62.8–74
Hurricane 74+ 119+

Sports Speed References

Sport / Context mph km/h
Average jogging 5–6 8–9.7
Usain Bolt top speed 27.8 44.72
Pro cycling sprint 45 72.4
Tennis serve (record) 163.7 263.4
Baseball pitch (fast) 100 160.9
NASCAR top speed 200 321.9
F1 top speed 230 370.1

Quick Mental Math

Multiply by 1.6 for a close approximation:

  • 60 mph × 1.6 = 96 km/h (exact: 96.56)
  • 100 mph × 1.6 = 160 km/h (exact: 160.93)

Use Case

An American driver renting a car in Europe needs to understand the speedometer readings in km/h by mentally converting from their familiar mph reference points.

Try It — Unit Converter

Open full tool