The present invention concerns a method for estimating a level of damage of an electric device. The method comprises the steps of: forming a histogram of operating cycles related to the electric device for which the level of damage estimation is performed, comparing the formed histogram to histograms of a collection of histograms or to combinations of histograms of the collection of histograms, each histogram of the collection of histogram being associated to a level of damage, in order to determine the histogram of the collection of histograms or the combination of histograms which is the closest from the formed histogram, determining an estimate of the level of damage of the electric device from the level of damage of the closest histogram or from the levels of damages of the histograms of the closest combination of histograms.