Live stage shows, fireworks, and the roar of a stadium crowd can reach dangerously high volumes—so high they might cause irreversible hearing loss. But what was the loudest sound ever recorded on Earth?
The answer depends on what you mean by “sound” and whether you consider old historical accounts or rely only on measurements taken with modern scientific instruments.
Volcanic Eruption
The 1883 eruption of the Indonesian volcanic island of Krakatoa (also known as Krakatau) is often cited as the loudest noise in history. People heard the blast from over 3 thousand kilometers away, and barometers worldwide registered its shock wave. At a distance of 160 kilometers, the eruption reached roughly 170 decibels—sufficient to cause permanent hearing loss. Sailors reported that at 64 kilometers away, the explosion was so powerful it could rupture eardrums.
Generally, people can endure sounds up to 140 decibels, after which the noise becomes painful and unbearable. According to the National Institute of Health, hearing damage can occur after several hours of exposure to 85 decibels, 14 minutes of exposure to 100 decibels, or two minutes of exposure to 110 decibels. For comparison: a vacuum cleaner registers about 75 decibels, a chainsaw around 110 decibels, and a jet engine approximately 140 decibels.
By contemporary estimates, Krakatoa’s explosion reached levels of about 310 decibels. At this level, sound waves no longer behave like normal sound (which causes particles to vibrate and creates areas of compression and rarefaction). Instead, near 194 decibels, they transform into shock waves—powerful pressure fronts that arise when something travels faster than the speed of sound. Krakatoa’s shock wave was so potent that it circled the planet seven times.
A volcanic eruption can damage hearing, photo: Rawpixel.com via Shutterstock
However, Michael Vorländer, a professor and head of the Institute of Hearing Technology and Acoustics at RWTH Aachen University in Germany, and president of the Acoustical Society of America, stated that we don’t actually know how loud the Krakatoa eruption was at its onset because no one was close enough to measure it.
Meteorite Impact
Another contender for the loudest sound is the 1908 Tunguska meteorite explosion over Siberia, which felled trees across hundreds of square kilometers and generated shock waves globally. The Tunguska impact was about as loud as Krakatoa,—around 300 to 315 decibels—but like Krakatoa, the Tunguska blast was only registered by instruments located very far away.
The Loudest Sound in the Modern Era
If the question is framed within the context of the modern era, meaning when scientists had a global network of barometers and infrasound sensors, a much more recent event takes the top prize.
“I believe the loudest sound ever recorded was the eruption of the Hunga Tonga volcano in January 2022,” said David Fee, a research professor at the Geophysical Institute at the University of Alaska Fairbanks. “This powerful volcanic eruption created a sound wave that circled the globe multiple times and was heard by people thousands of kilometers away, including in Alaska and Central Europe.”
Milton Garces, founder and director of the Infrasound Laboratory at the University of Hawaii, concurs: “If you rephrase the question to ‘What is the loudest sound detected in the modern digital epoch?’, then without doubt, the loudest sound was the one produced by Tonga in ’22.”
One of the scientific stations closest to the underwater eruption site, located in Nuku’alofa about 68 kilometers away, registered a pressure surge of about 1800 pascals. If you tried to translate this into standard “decibels” one meter from the source, you’d get around 256 decibels.
But Garces said that would be unscientific because it wasn’t a regular sound wave at all. Near the source, it was more akin to rapidly moving air pushed out by the explosion. The Tonga blast was simply too powerful to be measured in conventional decibels.
Artificial Sounds
Curiously, the most powerful shock wave in recent history was practically inaudible to humans, as it fell outside the range of human hearing.
Scientists have attempted to create waves of immense power in laboratories. In one experiment, researchers used an X-ray laser to generate a microscopic jet of water, which created a pressure wave estimated at around 270 decibels. This is even louder than the launch of the Saturn V rocket that took Apollo astronauts to the Moon—about 203 decibels.
However, the laser experiment took place in a vacuum chamber, so the 270-decibel pressure wave was completely silent. Sound waves require a medium, such as air, water, or a solid, to propagate.
Scientists also know the necessary volume level required to trigger an avalanche.
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