This is one of the fundamental methods for evaluating the condition of a rolling bearing. The crest factor is determined by the ratio between the peak value and the RMS value, which places it among the group of methods that process already measured values. Its high sensitivity is also used for monitoring lubricating films. However, its disadvantage is that in the case of severe bearing damage, its value can be very similar to an undamaged bearing. Therefore, it is always used as a complementary method. The crest factor should ideally range from 2 to 4. If this value is exceeded, it indicates emerging damage.