The loudest recorded sound ever heard is believed to be the eruption of the Krakatoa volcano in 1883. Located between the islands of Java and Sumatra in Indonesia, the eruption produced an extremely powerful sound that was heard over a vast distance.
The sound generated by the Krakatoa eruption was estimated to have reached an astonishing 180 to 190 decibels (dB) at a distance of 100 miles (160 kilometers) from the volcano. To put this into perspective, a typical rock concert or jet engine produces sound levels of around 120 dB, and prolonged exposure to sounds above 85 dB can cause hearing damage.
The Krakatoa eruption was so powerful that it resulted in a series of tsunamis and caused widespread destruction in the surrounding area. The sound waves created by the eruption traveled multiple times around the globe and were detected as far away as the Indian Ocean island of Rodrigues, about 3,000 miles (4,800 kilometers) from Krakatoa.
It's worth noting that the specific measurement of the Krakatoa eruption's sound is an estimate based on historical records and calculations. Since then, there have been no widely accepted instances of sounds reaching or exceeding the sound pressure levels produced by Krakatoa.