What Was the Loudest Sound Ever Recorded? From Krakatau to Hunga Tonga

What Was the Loudest Sound Ever Recorded?

Live concerts, fireworks and stadium crowds can reach levels that permanently damage hearing — but the question of the "loudest" sound ever recorded depends on what you mean by "sound." Are you counting historical eyewitness reports, inferred values from distant instruments, or modern direct measurements with global sensor networks?

Historical Candidates: Krakatau (1883)

The 1883 eruption of Krakatau (Krakatoa) in Indonesia is often cited as history's loudest explosion. Contemporary reports say the blast was heard more than 1,900 miles (3,000 km) away, and barometers worldwide detected its pressure wave. Estimates put the eruption at about 170 decibels at 100 miles (160 km) — loud enough to cause permanent hearing damage — and sailors reported eardrum-rupturing booms at roughly 40 miles (64 km).

For context, most people find sounds painful above about 140 dB. The U.S. National Institutes of Health notes hearing damage can occur after a few hours at 85 dB, about 14 minutes at 100 dB, or two minutes at 110 dB.

Some modern reanalyses suggest Krakatau's peak at the source could have been as high as ~310 dB. But decibel scales and conventional acoustic models break down well below that: around 194 dB in air, ordinary sound waves turn into shock waves — abrupt pressure fronts that behave differently from linear sound.

"We don't really know how loud the Krakatau eruption was at its source because no one was close enough to measure it," — Michael Vorländer, RWTH Aachen University.

Another Historical Contender: Tunguska (1908)

The Tunguska event — likely a meteor airburst over Siberia in 1908 — flattened trees across hundreds of square miles and produced pressure waves detected worldwide. Inferred peak values for Tunguska are similar to Krakatau, on the order of 300–315 dB, but like Krakatau these figures are extrapolations from distant observations rather than direct, close-in measurements.

Modern Era Champion: Hunga Tonga–Hunga Ha'apai (January 2022)

If you restrict the question to the modern instrument era — when an extensive network of barometers and infrasound sensors was available — the January 2022 underwater eruption of Hunga Tonga is the standout. The eruption produced a pressure wave that traveled around the globe multiple times and was heard thousands of miles away.

One station in Nuku'alofa, about 42 miles (68 km) from the eruption, recorded a pressure jump of roughly 1,800 pascals. Converting that overpressure into a conventional decibel level at 1 meter would give an enormous-sounding number (roughly ~256 dB), but that calculation is misleading: the event produced a shock-like displacement of air rather than a normal acoustic wave near the source, so standard dB metrics don't represent the physics well.

"If you reframe the question as 'loudest sound recorded in the modern digital epoch,' then without a doubt the loudest sound was from Tonga in '22," — Milton Garces, Infrasound Laboratory, University of Hawaii.

Much of the Tonga eruption's energy was at infrasound frequencies below human hearing, so people far away often did not "hear" the full energy even though instruments recorded massive pressure changes.

Laboratory Pulses And The Limits Of 'Decibels'

Scientists have generated extreme pressure pulses in controlled settings. An X-ray laser striking a microscopic water jet produced a pressure pulse estimated at about 270 dB — higher than the estimated 203 dB for a Saturn V rocket at close range — but that experiment occurred inside a vacuum chamber, so the pulse produced no audible sound in air. Sound requires a medium (air, water, or solid material) to propagate; vacuum pressures are not the same as audible sound in an atmosphere.

Bottom line: "Loudest" depends on your definition. For historical, narrative impact, Krakatau (1883) and Tunguska (1908) are prime contenders; for the modern, instrumented era, the Hunga Tonga eruption of 2022 produced the most powerful recorded pressure wave. Extreme overpressures and shock fronts, however, fall outside the straightforward decibel scale used for everyday sounds, and much of the energy from those events lies at infrasonic frequencies beyond human hearing.