A magnitude-7 earthquake releases about 32 times more seismic energy than a magnitude-6 earthquake.
Earthquake magnitude scales are logarithmic rather than linear. A one-unit increase corresponds to a tenfold increase in measured wave amplitude, but the associated energy increase is approximately 31.6 times, commonly rounded to 32.
This means a magnitude-8 earthquake releases roughly 32 times more energy than a magnitude-7 event and about 1,000 times more than a magnitude-6 event. The relationship applies to commonly used seismic magnitude estimates, including moment magnitude.
Magnitude is not the same as intensity. Magnitude describes the earthquake source, while intensity describes how strongly people and structures experience shaking at a particular location. Distance, soil conditions, building quality and depth can make intensities vary greatly during one earthquake.