Speed Converter
Instantly convert speed and velocity between automotive highway ratings (km/h & mph), scientific standards (m/s), maritime navigation (knots), and engineering units (ft/s).
100 km/h = 62.137119 mph
1 km/h = 0.621371 mph
Common Conversions
1 km/h =0.2778 m/s
1 km/h =0.6214 mph
1 km/h =0.54 kn
1 km/h =0.9113 ft/s
How Speed Conversions Work
Speed is the rate of distance traveled per unit of time. The SI base unit is the meter per second (m/s). Every common speed unit is converted into meters per second first, then converted into the target unit using exact international standards:
1 km/h = 1,000 m ÷ 3,600 s = 1 ÷ 3.6 m/s (0.277778 m/s)
1 mph = 1,609.344 m ÷ 3,600 s = 0.44704 m/s (exact)
1 knot = 1,852 m ÷ 3,600 s = 1.852 ÷ 3.6 m/s (0.514444 m/s)
Official Speed Standards & Ratios
| Unit | Symbol | Primary Domain | Exact Definition in m/s |
|---|---|---|---|
| Meters per Second | m/s | Scientific / SI Base | 1 m/s |
| Kilometers per Hour | km/h | Automotive / Global | 0.277777... m/s (1 / 3.6) |
| Miles per Hour | mph | Automotive / US & UK | 0.44704 m/s (exact) |
| Knot | kn | Aviation & Maritime | 0.514444... m/s (1.852 / 3.6) |
| Feet per Second | ft/s | Ballistics & Engineering | 0.3048 m/s (exact) |
Common Worked Examples
Example 1: Convert 100 km/h Highway Speed to mph
100 ÷ 1.609344 = 62.137119 mph.
Example 2: Convert 60 mph to km/h and m/s
60 × 1.609344 = 96.56064 km/h.
60 × 0.44704 = 26.8224 m/s.