Convert Mach numbers to km/h, m/s, mph, and knots.
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The Mach number (Mach) is a dimensionless quantity representing the ratio of an object's speed to the local speed of sound. Mach 1 corresponds to the speed of sound, which depends on air temperature and altitude — at sea level at 15 °C, this is approximately 1,225 km/h.
Common Mach Number Conversions
- Mach 1 ≈ 1,225 km/h — at sea level and 15 °C.
- Mach 1 = 340.29 m/s — standard speed of sound value.
- Mach 1 ≈ 761 mph — at sea level and 15 °C.
- Mach 1 ≈ 661 knots — at sea level and 15 °C.
Mach numbers are used in aviation and the aerospace industry. Subsonic speeds are below Mach 1, supersonic speeds range from Mach 1 to 5, and hypersonic speeds exceed Mach 5.