Speed Converter
Convert between mph, km/h, m/s, knots, and ft/s.
Last updated: June 13, 2026
Calculator
Results
How to Use This Calculator
- 1Enter the speed value.
- 2Select the unit you are converting from.
- 3View all equivalent speeds at once.
Formula Explanation
Speed units are converted through meters per second as the base unit.
Variables:
Worked Examples
60 mph to km/h
- 1. 1 mph = 1.60934 km/h
- 2. 60 × 1.60934 = 96.56 km/h
100 km/h to mph
- 1. 100 ÷ 1.60934 = 62.14 mph
Why Use This Calculator
- Convert between 5 speed units instantly.
- Essential for driving, aviation, sailing, and science.
- All conversions displayed at once.
- Handles very small and very large speeds.
Tips & Best Practices
- Quick mental math: mph × 1.6 ≈ km/h, and km/h × 0.6 ≈ mph.
- Speed of sound ≈ 767 mph = 1,235 km/h = 343 m/s.
- Knots are used in aviation and maritime — 1 knot = 1 nautical mile per hour.
Common Mistakes to Avoid
❌ Using "knots per hour" instead of "knots".
✅ A knot already means nautical miles per HOUR. Saying "knots per hour" implies acceleration, not speed.
❌ Assuming speed limits are the same number in different units.
✅ A 100 km/h limit (common in Europe) is only 62 mph. A 65 mph limit is 105 km/h.
Frequently Asked Questions
What is a knot?
How fast is Mach 1?
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<iframe src="https://redicalc.com/embed/math/speed-converter" width="100%" height="600" style="border:none;border-radius:12px;box-shadow:0 1px 3px rgba(0,0,0,0.1);" title="Speed Converter — RediCalc.com" loading="lazy" allowtransparency="true"></iframe>Disclaimer: This calculator is provided for informational and educational purposes only. Results are estimates and should not be used as a substitute for professional advice. RediCalc.com makes no guarantees regarding the accuracy, completeness, or suitability of any calculations. Always consult a qualified professional before making financial, health, construction, or other important decisions.
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