The crest factor of a waveform is given by the ratio of the peak to RMS amplitude level

Enter

- Peak amplitude
- Root-mean-square Amplitude

**Formula**

**CF = V _{peak}/V_{RMS}**

**Example Calculation**

If the peak value is 1V and RMS value is 0.707, then the Crest factor is 1.414 or 3 dB (using the volt to dB calculator). These are the values for a sine wave [1].

The crest factor for an OFDM waveform is quite a bit higher at 4 or 12 dB.

**References**

[1] Crest factor on Wikipedia