Convert between speed units instantly, plus running pace calculator
Multiply km/h by 0.621371. For example, 100 km/h ≈ 62.14 mph.
1 knot = 1.852 km/h. Used in aviation and maritime navigation.
Enter your distance and time. The calculator shows min/km and min/mi automatically.
Speed = distance per time (km/h). Pace = time per distance (min/km). Runners typically use pace.
Mach 1 ≈ 1,235 km/h or 767 mph at sea level, 15°C.
299,792,458 m/s or approximately 1,079,252,849 km/h.
For 5 min/km: speed = 60/5 = 12 km/h. For 8 min/mi: speed = 60/8 = 7.5 mph.
Yes, completely free. All calculations run in your browser.