Richter scale

Named after American seismologist Charles Richter (1900–1985), whose name derives from German Richter (“judge”).

• (US, Canada) IPA^(key): /ˈɹɪkt.ɚ skeɪl/

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the Richter scale

1. (seismology) A logarithmic scale used to express the energy released by an earthquake, each increase of 1 representing a 31-fold increase in energy, and a 10-fold increase in the measured wave amplitude.
   • 2025 March 28, Nicola Davis, quoting Bill McGuire, “What caused Myanmar and Thailand earthquake and how big was it?”, in The Guardian‎^[1], →ISSN:

     “The Richter scale is an old scale developed for California. It is only good for smaller quakes, and is not very good at differentiating the sizes of bigger shocks,” said McGuire.

Now mostly replaced by the moment magnitude scale, which is often incorrectly referred to as Richter scale in news media.

Richter scale (plural Richter scales)

1. A value on the Richter scale.

   The students also faced and experienced earthquakes at various Richter scales.

• Fujita scale
• Torino scale
• moment magnitude scale