How many kilometers per hour is 1 Mach?

Object’s speed
Speed of sound  =  Mach number

In other words, an aircraft moving just as fast as the speed of sound is traveling at Mach 1.

Mach 1 is ca. 1220 km/h. It is impossible to determine an exact conversion rate from Mach to km/h as the speed of sound depends on physical conditions in a given location such as: air temperature, humidity and pressure.

Aircrafts are roughly divided into several categories according to the speed at which they can travel:

Subsonic: Mach <1

Transonic: Mach = 1

Supersonic: Mach 1-5

Hypersonic: Mach 5-10

Hypervelocity: Mach >10

Did you know?

Sonic boom is the name for the noise that can be heard when an aircraft breaks the barrier of sound. It sounds similar to an explosion and may be even as loud as 200 decibels. The sound is produced because the air can’t ‘get out of the way’ of the aircraft fast enough and creates a shockwave.

A phenomenon which frequently accompanies aircraft sonic booms is a vapour cone (air getting compressed and forming a visible conical shape).

Did you know that a miniature sonic boom is produced when a whip cracks, too?