Enter a speed in mph (or other units) or a Mach number to convert to the other value using sea-level, temperature, or altitude options for the speed of sound.
Miles to Mach Formula
The following formulas convert miles per hour to Mach and back, either at standard sea level or using the general definition with the local speed of sound.
\mathrm{Mach} = \frac{v}{a}- Standard sea level (15°C): a ≈ 340.29 m/s ≈ 761.2 mph.
- mph to m/s: 1 mph = 0.44704 m/s.
- Definition: Mach (M) = speed ÷ speed of sound (v ÷ a).
- Inverse: speed = Mach × a.
Miles to Mach Conversion Table
| Miles per hour (mph) | Mach |
|---|---|
| 60 | 0.079 |
| 100 | 0.131 |
| 200 | 0.263 |
| 300 | 0.394 |
| 400 | 0.525 |
| 500 | 0.657 |
| 600 | 0.788 |
| 700 | 0.919 |
| 750 | 0.985 |
| 761.2 | 1.000 |
| 800 | 1.051 |
| 900 | 1.182 |
| 1000 | 1.314 |
| 1200 | 1.576 |
| 1500 | 1.971 |
| 1800 | 2.365 |
| 2000 | 2.628 |
| 2500 | 3.284 |
| 3000 | 3.942 |
| 5000 | 6.568 |
| * Standard sea level (15°C): 1 Mach ≈ 761.2 mph (≈ 340.29 m/s). | |
How do you convert miles per hour to Mach? Divide mph by the speed of sound in mph (≈ 761.2 at 15°C sea level), or more generally use Mach = v ÷ a with a based on temperature/altitude.
How do you convert Mach to miles per hour? Multiply Mach by the local speed of sound (in mph), which depends on the environment; at 15°C sea level, mph ≈ Mach × 761.2.
Example Problem
Convert 1,200 mph to Mach at standard sea level (15°C).
Use the formula: Mach = v ÷ a, where a ≈ 761.2 mph at sea level.
Mach = 1200 ÷ 761.2 ≈ 1.576