Glossary definition of 'Crest factor'

The ratio the peak of a waveform (crest of a wave) to its RMS value. For random signals this needs to be measured over a specified time interval. For repeating signals, this needs to be measured over one cycle. A sine wave has a crest factor of 1.414 or √2 since the peak is 1.414 × the RMS value. This can also be expressed as 3.01dB.