On August 27, 1883, the Indonesian volcano Krakatoa erupted with such force that it produced the loudest sound ever recorded in human history. At 10:02 am, a massive explosion was heard across an astonishing distance of 4,800 kilometres, from Mauritius in the Indian Ocean to Australia.

The blast was so powerful that it burst the eardrums of sailors on nearby ships and was captured on barometers all over the world. The eruption did not just destroy an island; it changed the planet’s atmosphere and climate for years to come.

Scientists estimate that the eruption unleashed energy equal to 200 megatons of TNT, about 10,000 times stronger than the atomic bomb dropped on Hiroshima. It was even four times more powerful than Tsar Bomba, the largest nuclear bomb ever tested.

The explosion wiped out two-thirds of Krakatoa Island and caused tsunamis as high as 46 metres (151 feet). These waves hit the coasts of Java and Sumatra, destroying over 160 villages. More than 36,000 lives were lost, and thousands more were displaced.

The sound waves from Krakatoa’s eruption circled the Earth multiple times. In London, barometers showed sudden pressure changes as the shockwaves traveled around the globe again and again.

Ash from the eruption shot 25 kilometres into the sky, blocking sunlight and leading to a “volcanic winterW.” Temperatures around the world dropped, and crop failures brought food shortages in many regions.

Other powerful sounds in history

While Krakatoa holds the record for the loudest sound, other events have also created earth-shaking noise.

  • In 1886, New Zealand’s Mount Tarawera erupted, and the sound carried more than 1,000 kilometres away.

  • In 1908, the Tunguska meteor blast in Siberia flattened 2,000 square kilometres of forest with its shockwaves.

  • In 1980, Mount St. Helens in the United States erupted, with an explosion heard 320 kilometres away.

  • Even underwater, huge events like the 1961 Tsar Bomba test and the 2022 Hunga Tonga-Hunga Ha’apai volcanic eruption created sounds that travelled across continents.

The Krakatoa eruption left more than destruction; it reshaped science itself. The worldwide recordings of its sound waves and atmospheric pressure changes gave researchers new tools to study volcanoes and earthquakes.

Krakatoa remains a reminder of nature’s raw power, a single explosion that shook the Earth, changed its skies, and was heard across nearly one-eighth of the planet.