The 1960 Valdivia earthquake had a magnitude of 9.5, making it the largest earthquake ever recorded by modern instruments.
Also called the Great Chilean earthquake, it struck southern Chile on May 22, 1960, along the subduction zone where the Nazca Plate dives beneath the South American Plate. The rupture extended for roughly 1,000 kilometers and lasted about 10 minutes, releasing enormous energy.
The earthquake generated a Pacific-wide tsunami. Waves devastated coastal areas in Chile and reached Hawaii, Japan, the Philippines, New Zealand, and other Pacific locations. The disaster caused thousands of deaths, although estimates vary widely because records were incomplete.
A common mix-up is confusing the earthquake’s magnitude with tsunami wave height or intensity. Some scientific studies give the event a range around 9.4–9.6, but 9.5 is the standard rounded figure used in trivia, reference works, and earthquake comparisons.