⚡ Speed Converter
Convert between mph, km/h, knots, and more
Quick Reference
1 km/h = 0.6214 mph
1 mph = 1.6093 km/h
1 knot = 1.852 km/h
Speed of sound ≈ 343 m/s ≈ 1,235 km/h
Speed of light ≈ 299,792,458 m/s
How Speed Conversion Works
- 1Enter a speed value in any supported unit.
- 2Select the source unit (mph, km/h, m/s, knots, etc.).
- 3The converter uses standard conversion factors between units.
- 4All speed units are calculated and displayed simultaneously.
- 5Common conversions: 1 mph = 1.609 km/h = 0.447 m/s.
About Speed Converter
Convert between speed units: mph, km/h, m/s, knots, feet per second, and Mach. Instant bidirectional speed conversion for travel, science, and aviation calculations.
Frequently Asked Questions
How do I convert mph to km/h?
Multiply mph by 1.60934. For example, 60 mph = 96.56 km/h. For a quick estimate, multiply by 1.6.
What is a knot?
A knot is one nautical mile per hour (1.852 km/h or 1.151 mph). It's used in aviation and maritime navigation because it relates directly to latitude degrees.
What speed is Mach 1?
Mach 1 is the speed of sound, approximately 767 mph (1,235 km/h) at sea level and 68°F. It varies with temperature and altitude — at 35,000 ft it's about 660 mph.