Understanding the Richter Scale

The Richter scale is a logarithmic scale used to measure the magnitude of earthquakes. Developed in 1935 by Charles F. Richter, it quantifies the energy released at the earthquake’s source.

How the Scale Works

Each whole number increase represents 10 times more shaking and about 32 times more energy. For example:

• A magnitude 5.0 releases 32 times more energy than a 4.0
• A magnitude 6.0 releases 1,000 times more energy than a 4.0

Typical Effects by Magnitude

• 2.0–3.0: Usually not felt
• 4.0–5.0: Light shaking, minor damage
• 6.0–7.0: Strong shaking, moderate damage
• 7.0–8.0: Major damage in affected areas
• 8.0+: Severe, widespread destruction

Modern Alternatives

Today, seismologists often use the Moment Magnitude Scale (Mw), which is more accurate for large earthquakes, but the term “Richter scale” remains widely recognised.