Convert Mach (SI Standard) (Ma) to Mach (20°C, 1 atm) (Ma (20°C)) instantly.
About these units
Mach (SI Standard) (Ma)
Mach is a dimensionless measure of speed relative to the speed of sound in a given medium. Mach 1 corresponds to the speed of sound, Mach 2 is twice that speed, and so on. Mach values change with temperature, atmospheric pressure, and altitude because the speed of sound changes with these conditions. Aircraft performance, supersonic flight, rocket design, and shockwave analysis all depend heavily on Mach numbers. Mach is more than just a speed measure—it categorizes aerodynamic regimes: Subsonic (Mach < 1), Transonic (Mach 0.8–1.2), Supersonic (Mach 1–5), Hypersonic (Mach > 5). Mach numbers therefore provide insight into aerodynamic behavior, not just velocity.
Mach (20°C, 1 atm) (Ma (20°C))
At 20°C and 1 atmosphere, the speed of sound in air is about 343 m/s, making Mach 1 = 343 m/s under those conditions. Mach numbers classify aerodynamic regimes: Mach 0.3–0.8 (Subsonic), Mach 0.8–1.2 (Transonic), Mach 1–5 (Supersonic), Mach 5+ (Hypersonic). Temperature influences Mach speed significantly; colder air slows sound, while warmer air increases its speed. Aircraft design, jet engines, wind tunnels, aerospace testing, and atmospheric re-entry physics all rely heavily on Mach numbers referenced to standard conditions.