A gunshot typically produces 140 to 170 decibels of peak sound pressure, depending on the firearm and ammunition. That makes it one of the loudest sounds most people will ever encounter, and every common firearm exceeds the 140 dB threshold where a single exposure can cause permanent hearing damage.
Decibel Levels by Caliber
Not all gunshots are equally loud. Barrel length, caliber, and ammunition type all affect the peak sound pressure. Here’s how common firearms compare, measured at the shooter’s ear:
- .22 LR rifle: 139 to 144 dB. The quietest common firearm round, though still at or above the danger threshold.
- .22 LR pistol: 154 to 158 dB. The same cartridge in a short-barreled handgun is significantly louder because the powder gases have less barrel to expand in before hitting open air.
- 9mm pistol: 160 to 163 dB. A Glock 17, one of the most popular handguns in the world, measures around 163 dB.
- .45 ACP pistol: 159 to 166 dB.
- .223/5.56mm rifle (AR-15): 159 to 171 dB.
- .308/7.62mm rifle: 159 to 173 dB. Among the loudest common sporting rounds.
- 12-gauge shotgun: 152 to 161 dB, varying with shell length and choke type.
The pattern is straightforward: bigger powder charges and shorter barrels mean more noise. A compact handgun firing the same round as a full-size rifle will almost always be louder, because the expanding gases exit the muzzle at higher pressure.
Why Gunshots Are So Dangerous to Hearing
Decibels work on a logarithmic scale. Every 10 dB increase represents a tenfold increase in sound energy. A 160 dB gunshot isn’t just a little louder than a 100 dB jackhammer; it’s roughly a million times more intense in terms of sound pressure.
OSHA’s noise standard sets 140 dB as the ceiling for impulse noise exposure without hearing protection. Above that level, permanent hearing loss can occur from direct mechanical damage to the structures of the inner ear, not just from prolonged exposure but from a single shot. Every firearm on the list above meets or exceeds that threshold. A 9mm handgun at 163 dB is more than 20 dB over the safety limit, which means it delivers over 100 times the sound energy considered safe.
For context, a jet engine at 30 meters produces about 150 dB, and a jackhammer at one meter hits roughly 100 dB. Most gunshots are louder than standing near a jet engine.
What Creates the Sound
A gunshot produces two distinct sounds. The first is the muzzle blast: a burst of high-pressure gas that exits the barrel behind the bullet and slams into the surrounding air. This is the deep boom or sharp bang that makes up most of the noise, and it’s the component that hearing protection and suppressors primarily target.
The second component is the supersonic crack of the bullet itself. Any bullet traveling faster than the speed of sound (about 1,125 feet per second at sea level) creates a small sonic boom as it moves through the air. This crack is what you hear downrange as a sharp, whip-like snap. Subsonic ammunition eliminates this component, which is why it’s often paired with suppressors for maximum noise reduction.
How Much Do Suppressors Help
Suppressors reduce gunshot noise by 20 to 35 dB on average. That brings a typical gunshot down to roughly 120 to 140 dB, depending on the caliber. A suppressed .22 LR pistol can get into the 115 dB range, which is roughly the volume of a loud rock concert. A suppressed 9mm or .308 typically lands between 130 and 140 dB.
Even the best suppressors on the market rarely bring the sound below 110 dB, and most suppressed centerfire guns remain above the 140 dB damage threshold. The Hollywood version of a silencer producing a soft “pfft” is fiction. What suppressors actually do is take the noise from instantly damaging to something that’s still very loud but far less likely to cause permanent injury from a single exposure, especially when combined with hearing protection.
Why Standard Hearing Protection Falls Short
The Noise Reduction Rating (NRR) printed on a box of earplugs or earmuffs is tested using steady, continuous sound at moderate levels. Gunshots are a completely different animal: extremely brief impulses at very high peak pressures. Research from Westone’s acoustics lab found that NRR numbers don’t reliably predict how well a protector performs against gunshot-level impulse noise.
A more accurate measurement is called Impulsive Peak Insertion Loss (IPIL), which tests protection at the actual sound levels firearms produce. In one example, a hearing protector with an NRR of just 4 dB actually reduced a 170 dB impulse by 26.7 dB when measured using the IPIL method, bringing the exposure down to about 143 dB. That’s useful, but it still leaves the wearer above the 140 dB safety limit from a single shot.
This is why NIOSH recommends dual hearing protection (earplugs under earmuffs) for any shooting environment where noise exceeds 140 dB. Since virtually every firearm exceeds that level, doubling up is the safest approach for anyone who shoots regularly. A well-fitted combination of foam earplugs and over-ear muffs provides meaningfully more protection than either one alone, particularly against the extreme peak pressures of rifle and magnum calibers.
Distance Makes a Difference
All the measurements above are taken near the shooter’s position. Sound pressure drops as you move away from the source, roughly following the inverse square law: doubling your distance cuts the intensity significantly. A gunshot that measures 163 dB at the muzzle will be substantially quieter at 50 or 100 meters, though still easily audible at a mile or more depending on terrain and atmospheric conditions.
For bystanders and neighbors near shooting ranges, the relevant number isn’t the peak level at the muzzle but the reduced level at their actual distance. Even so, the starting point is so high that gunshots can remain above safe levels for anyone within several dozen meters without protection.