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Earthquake Magnitude Comparison

Enter two magnitudes to calculate the ratio of energy released by each earthquake. Compare scales intuitively, such as about 32× per magnitude and 1,000× for two.

Input

Enter two magnitudes to estimate the ratio of energy released by each earthquake. A magnitude that is 1 larger releases about 32 times more energy, and 2 larger releases about 1,000 times more.

Result

Energy ratio (larger ÷ smaller)

1,000×

The M9.0 earthquake releases about 1,000× the energy of the M7.0 earthquake.

Magnitude difference

2.0

Energy ratio

1,000×

Energy of M9.0

approx. 2.00×10^18 J

Energy of M7.0

approx. 2.00×10^15 J

Energy ratio = 10^(1.5×(M1−M2)). Each energy is estimated from log10(E)=4.8+1.5M (E in joules).

Magnitude difference and energy ratio guide

Magnitude differenceEnergy ratioGuide
0.22.00×about 2×
0.55.62×about 5.6×
1.031.6×about 32×
2.01,000×1,000×
3.031,623×about 32,000×

* Actual values vary with the type of magnitude scale and calculation method. Results are estimates only; for disaster prevention and earthquake decisions, refer to official sources such as your national meteorological agency.

How it works

  • The energy ratio is calculated as E1÷E2 = 10^(1.5×(M1−M2)). For every 1 unit of magnitude difference, the energy increases by about 31.6 times (roughly 32 times).
  • A magnitude that is 2 larger releases 1,000 times more energy, and 3 larger releases about 32,000 times more. Because magnitude is defined on a logarithmic scale of energy, even a small difference changes the released energy dramatically.
  • Each earthquake's energy (in joules) is estimated using the Gutenberg-Richter relation log10(E)=4.8+1.5M, where E is in joules.
  • This tool compares the energy released by earthquakes, which differs from seismic intensity (how strong the shaking feels) or the actual damage experienced at the surface.
  • There are several magnitude scales, such as moment magnitude (Mw) and the JMA magnitude (Mj), and values differ by calculation method, so treat the results as estimates.
  • The displayed values are approximations. For specific decisions about disaster prevention or earthquakes, always refer to official sources such as your national meteorological agency.