Great earthquakes · One-click replays
The Biggest Earthquakes Ever Recorded
Every earthquake in this list is built into the animator as a one-click preset. Choosing one loads the real USGS catalog for that event's region and time window — so you do not just see the mainshock, you watch the entire aftershock sequence unfold over the following weeks and months, in three dimensions.
The ten largest instrumentally recorded earthquakes
| # | Earthquake | Magnitude | Date |
|---|---|---|---|
| 1 | Valdivia, Chile | 9.5 | 22 May 1960 |
| 2 | Good Friday, Alaska | 9.2 | 28 March 1964 |
| 3 | Sumatra–Andaman | 9.1 | 26 December 2004 |
| 4 | Tōhoku, Japan | 9.1 | 11 March 2011 |
| 5 | Kamchatka, Russia | 9.0 | 4 November 1952 |
| 6 | Kamchatka, Russia | 8.8 | 29 July 2025 |
| 7 | Maule, Chile | 8.8 | 27 February 2010 |
| 8 | Ecuador–Colombia | 8.8 | 31 January 1906 |
| 9 | Rat Islands, Alaska | 8.7 | 4 February 1965 |
| 10 | Assam–Tibet, India | 8.6 | 15 August 1950 |
Magnitudes for older events are estimates derived from the seismograms available at the time, and different agencies publish slightly different values. Rankings around the 8.6–8.8 range shift depending on which catalog you consult.
Every one of them is a subduction megathrust
With the partial exception of Assam–Tibet — a continental collision zone where India drives into Eurasia — this entire list comes from one setting: a subduction zone megathrust, the low-angle contact where one plate descends beneath another.
The reason is geometric. Magnitude is a function of rupture area multiplied by slip. Megathrusts offer the largest continuous fault surfaces on the planet — a thousand kilometres long and well over a hundred wide. A strike-slip fault like the San Andreas simply cannot present enough area to reach magnitude 9, no matter how far it slips. If you want to know where the next great earthquake will be, the answer is: along the convergent boundaries.
Three worth watching closely
Valdivia, Chile — M9.5, 1960
The largest earthquake ever measured. Around 1,000 km of the Chilean subduction zone ruptured, dropping and lifting the coastline by metres and generating a tsunami that crossed the entire Pacific — killing people in Hawaii, Japan and the Philippines a day later. The preset runs from March to September 1960, so the foreshock sequence is included as well as the aftershocks.
Sumatra–Andaman — M9.1, 2004
A rupture that propagated north for roughly 1,300 km over about ten minutes, one of the longest ever recorded. The resulting Indian Ocean tsunami killed almost a quarter of a million people across fourteen countries. Watching the six-month aftershock window animate is the clearest illustration of rupture length in the whole preset list — the aftershocks trace the full arc of the break.
Tōhoku, Japan — M9.1, 2011
The best-instrumented great earthquake in history, striking the most densely monitored subduction zone on Earth. The aftershock sequence is correspondingly dense: thousands of recorded events in the following months, filling in the rupture zone off the coast of Honshu. It is the best preset for seeing what a modern seismic network actually captures.
Catalog completeness varies enormously by era. Seismic networks were small in the 1950s and 60s, so older events list far fewer aftershocks — not because fewer occurred, but because fewer were detected. Dense small-magnitude coverage exists mainly for the United States; you will not find magnitude 1 events in most of the world's catalog at any date.
What to look for in a replay
- Aftershock decay. Activity is furious in the first hours, then falls off following a predictable pattern (Omori's law). Slow the animation down to watch the first day properly.
- Rupture extent. Aftershocks cluster around the area that actually broke, so the aftershock cloud is effectively a map of the rupture surface.
- Depth structure. Switch to cross-section and the aftershocks resolve onto the dipping slab interface — see earthquake depth.
- Foreshocks. Several presets start weeks before the mainshock. Tōhoku had a notable M7.3 foreshock two days prior.
Common questions
What is the biggest earthquake ever recorded?
The largest earthquake ever recorded by instruments was the magnitude 9.5 Valdivia earthquake in Chile on 22 May 1960. It ruptured roughly 1,000 kilometres of the subduction zone off the Chilean coast and generated a Pacific-wide tsunami that caused deaths as far away as Hawaii, Japan and the Philippines.
Why are all the largest earthquakes at subduction zones?
Magnitude scales with the area of fault that ruptures multiplied by how far it slips. Subduction megathrusts are by far the largest fault surfaces on Earth — low-angle contacts that can be a thousand kilometres long and well over a hundred kilometres wide. No other fault type offers enough surface area to reach magnitude 9.
Are earthquakes getting more frequent?
There is no established evidence that large earthquakes are becoming more frequent. What has changed dramatically is detection: seismic networks have expanded enormously since the mid-20th century, so far more events are recorded and reported now. Global rates of magnitude 7 and above have remained broadly steady over the period we can measure reliably.
Why do older historic earthquakes show fewer aftershocks?
Because the seismic networks of the time were far smaller. A 1950s earthquake was recorded by a fraction of the instruments available today, so only the larger aftershocks entered the catalog. The sparse aftershock cloud around older events reflects the limits of historic monitoring, not a genuinely quieter sequence.