What does each magnitude of earthquake really mean?
Earthquakes are measured on a scale up to 10 on the moment magnitude scale, with the higher the number meaning more significant impacts.
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Earthquakes happen all over the world every single day, with some never felt at all and others destroying entire cities. But what does that measurement actually mean?
Earthquakes are measured on a scale up to 10 on the moment magnitude scale, with the higher the number meaning more significant impacts.
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The moment magnitude scale largely replaced the Richter scale for measuring earthquakes. Magnitude is expressed in whole numbers and decimal fractions.
Moment magnitude scale vs Richter scale for earthquakes. (FOX Weather)
It's an accurate measure of the total energy of an earthquake, rather than the measure of a single point of surface energy, like the Richter scale.
Each whole number increase on the moment magnitude scale represents 32 times more energy release, according to the U.S. Geological Survey (USGS).
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Earthquake magnitude explainer
The deeper an earthquake is reported beneath the surface, the less likely it is to be felt.
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Find out what each magnitude means:
Magnitudes 1 and 2:
Any earthquake below a magnitude 2 is very unlikely to cause any damage or be felt by people.
However, the higher you get on the magnitude 2 scale (2.1 to 2.9), the more likely it is to be felt.
The USGS' latest earthquake database only shows magnitude 2.5 or higher by default, as magnitude 2.5 is typically one of the lowest magnitudes that can be felt by people.
Magnitudes 3 to 5:
Earthquakes that are between magnitude 3 and 5.9 are very likely to be felt, especially close to the epicenter of the earthquake.
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GRANADA ANDALUSIA,, SPAIN - AUGUST 15: Impact of the magnitude 5.2 earthquake on buildings and homes in the city of Granada. 15 August 2026 in Granada (Andalusia, Spain). (Francisco J. Olmo/Europa Press / Getty Images)
The stronger the magnitude, the more likely it is to cause damage as well, though with magnitudes 3 to 5, minor damage is typically all that's possible.
These earthquakes are typically considered as minor to moderate earthquakes.
Magnitude 6:
When an earthquake is reported as a magnitude 6, it is likely to cause damage to buildings.
Magnitude 6 earthquakes are officially rated as "strong" earthquakes, entering the territory before a "major" earthquake.
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BALIKESIR, TURKIYE - OCTOBER 28: A general view shows the collapsed building after a 6.1 magnitude earthquake struck in the Sindirgi district at 22:48 local time on October 28, 2025, in Balikesir, Turkiye. (Mehmet Emin Menguarslan/Anadolu / Getty Images)
Earthquakes below magnitude 6.5 are very unlikely to trigger a tsunami, the USGS said.
Magnitude 7:
A magnitude 7 earthquake is considered a major earthquake.
These earthquakes are more likely to cause major damage in populated areas, leaving collapsed buildings and damaged infrastructure.
The USGS said earthquakes between magnitude 6.5 and 7.5 are unlikely to produce a destructive tsunami, but small sea level changes might be recorded near the earthquake's epicenter.
However, earthquakes between magnitude 7.6 and 7.8 could produce a destructive tsunami, especially near the epicenter.
When a magnitude 7.9 or greater earthquake happens, the USGS said, destructive local tsunamis are possible near the epicenter, and significant sea level changes and damage might occur in a wider region.
Magnitude 8:
Anything stronger than a magnitude 8 earthquake is considered a "great" earthquake capable of causing catastrophic damage.
Some of the largest earthquakes ever recorded have been in the high magnitude 8 range.
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A screen grab from a video shows rescuers of the Ministry of Emergency Situations of Russia inspecting a damaged building after magnitude 8.8 earthquake hits Kamchatka Peninsula on July 30, 2025 in, Russia. (Emergency Situations of Russia / Handout/Anadolu / Getty Images)
For example, in 2025, a magnitude 8.8 earthquake rattled Kamchatka, Russia, causing a tsunami to make its way across the Pacific, impacting Hawaii and the U.S. West Coast.
It was also the seventh-largest earthquake to be reported since 1900, according to the USGS.
Magnitude 9+:
Any earthquake in the magnitude 9 or above range is going to be one of the strongest earthquakes ever recorded.
Five of the top 10 earthquakes recorded by the USGS since 1900 are a magnitude 9.0 or larger.
KESENNUMA, JAPAN - MARCH 16: A rescue worker stands in the rubble of a village destroyed by the devastating earthquake, fires and tsunami March 16, 2011 in Kesennuma, Miyagi province, Japan. (Paula Bronstein / Getty Images)
Earthquakes this strong are exceptionally rare.
The largest earthquake ever was a magnitude 9.5, which occurred in Chile in 1960. It is commonly referred to as the Great Chilean earthquake and killed 1,655 people and left two million homeless, according to the USGS.
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The most recent magnitude 9 earthquake occurred in 2011 in Japan, when a magnitude 9.1 earthquake and tsunami killed more than 15,000 people and displaced 130,000 more.
Local residents look at a mountain of debris left by the March 11 tsunami and earthquake in Natori in Miyagi Prefecture on March 16, 2011. (TORU YAMANAKA / AFP / Getty Images)
It's important to understand that earthquakes of smaller magnitudes can still be dangerous in some areas. The more damage an earthquake causes is typically dependent on how strong the infrastructure is.
"There have been large earthquakes with very little damage because they caused little shaking and/or buildings were built to withstand that shaking," the USGS said.
Earthquakes themselves don't kill people, buildings and their contents do.
If you ever experience an earthquake, practice the "drop, cover and hold on" technique, which means drop to the floor, make yourself small and get under a sturdy piece of furniture, cover your neck and head with one arm and hold onto the furniture with the other until the shaking stops.