How it’s calculated
Speeds are converted through meters per second.
1 mph = 1,609.344 m / 3,600 s = 0.44704 m/s
1 km/h = 1,000 / 3,600 m/s ≈ 0.277778 m/s
1 knot = 1 nautical mile per hour = 1,852 / 3,600 m/s
1 ft/s = 0.3048 m/s
km/h = mph × 1.609344
Example: 60 mph × 1.609344 = 96.56 km/h (26.82 m/s).
Frequently asked questions
How do I convert mph to km/h?
Multiply by 1.609344. For example, 70 mph ≈ 112.65 km/h. To go back, divide km/h by 1.609344 (100 km/h ≈ 62.14 mph).
What is a knot?
One nautical mile (exactly 1,852 m) per hour, about 1.15078 mph or 1.852 km/h. It is used at sea and in aviation.
How do I convert km/h to m/s?
Divide by 3.6. For example, 36 km/h = 10 m/s.
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Sources
- NIST Guide to the SI, Appendix B: Conversion Factors (SP 811) — U.S. National Institute of Standards and Technology
- The International System of Units (SI Brochure) — BIPM
Formulas are taken from the free public references above. Results are provided “as is” for informational and educational purposes only. See our disclaimer.
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