About the Muzzle Velocity Calculator
Our muzzle velocity calculator is designed to help firearm enthusiasts, ballistics experts, and hobbyists determine the speed at which a projectile exits the firearm barrel. Knowing muzzle velocity is critical in understanding a firearm's performance, as it influences accuracy, energy, and trajectory.
This bullet velocity calculator uses three approaches to finding muzzle velocity. Read the following article to learn more about them and to find out what muzzle velocity is or what an average bullet speed is.
🙋 We also have an FAQ section at the end of the text. Check it to discover interesting numbers related to projectile speed, such as the 9mm muzzle velocity!
What is muzzle velocity?
The muzzle velocity is the speed of the bullet that leaves the muzzle of a firearm, i.e., the end of the barrel.
The average bullet speed typically varies between 1000 ft/s (300 m/s) for handguns and 3900 ft/s (1200 m/s) for rifles. Large vehicles, such as tanks, can use bullets with even greater velocity, surpassing 5000 ft/s (1500 m/s).
Muzzle velocity calculator: bullet kinetic energy
Our tool uses three equations to determine the average bullet speed. The first one is based on the kinetic energy formula:
v = √(2 × KE / m)
- v — Muzzle velocity;
- KE — Bullet kinetic energy; and
- m — Bullet mass.
🔎 The muzzle velocity calculator will do all the unit conversions in the background, so you don't need to worry about it.
Bullet velocity calculator: barrel pressure
The second approach finds muzzle velocity from the pressure of the expanding gases inside the barrel. The work done by the gas as it pushes the bullet down the barrel equals the bullet's kinetic energy, which gives:
v = √(2 × P × A × L / m)
A = π × (d / 2)²
- P — Average pressure inside the barrel;
- A — Cross-sectional area of the bore, found from the caliber d;
- L — Barrel length; and
- m — Bullet mass.
This model assumes a constant average pressure over the whole barrel, so it gives a good estimate rather than an exact value.
How fast does a bullet travel?
The third approach is the most direct one — if you measure the distance a bullet covers and the time it takes (for example, with a chronograph), the speed is simply distance divided by time:
v = d / t
- d — Distance the bullet travels; and
- t — Time it takes to cover that distance.
Choosing your units — metric & US customary
This calculator supports both the metric (SI) and the US customary / imperial systems. Pick your preferred system, and the input and output units update automatically:
| Quantity | Metric (SI) | US customary |
|---|---|---|
| Kinetic energy (KE) | J (joules) | ft·lb (foot-pounds) |
| Bullet mass (m) | g (grams) | gr (grains) |
| Barrel pressure (P) | MPa (megapascals) | psi |
| Caliber (d) | mm | in (inches) |
| Barrel length (L) | cm | in (inches) |
| Distance (d) | m | ft (feet) |
| Muzzle velocity (v) | m/s | ft/s |
Whatever you enter, the result is shown in m/s, ft/s, km/h, mph, and as a Mach number (relative to the speed of sound, ≈ 343 m/s).
Step-by-step example
Kinetic energy method
A 9mm bullet has a kinetic energy of 580 J and a mass of 7.5 g (0.0075 kg).
v = √(2 × KE / m)
v = √(2 × 580 / 0.0075)
v = ≈ 393 m/s (1289 ft/s)
FAQs
- What is muzzle velocity? — It is the speed of a bullet at the moment it leaves the muzzle (the end of the barrel) of a firearm.
- What is the average bullet speed? — Handguns are usually around 1000 ft/s (300 m/s), while rifles can reach 3900 ft/s (1200 m/s) or more.
- What is the 9mm muzzle velocity? — A typical 9mm Parabellum round leaves the barrel at roughly 1100–1300 ft/s (340–400 m/s), depending on the load and barrel length.
- How do I calculate muzzle velocity from kinetic energy? — Use v = √(2 × KE / m), where KE is the kinetic energy and m is the bullet mass.
- Does barrel length affect muzzle velocity? — Yes. A longer barrel lets the expanding gas push the bullet for longer, generally increasing muzzle velocity up to a point.
- Is a faster bullet always better? — Not necessarily. Higher velocity improves flat trajectory and energy, but the ideal speed depends on the application, accuracy, and the target.