The choice of a bandwidth can affect dramatically the accuracy of classification methods relying on it. Recently, a large number of methods to choose the bandwidth have been developed. This article presents a simple method called KBER to estimate the bandwidth using the average Ricci curvature of ɛ− graphs. The Radial Basis Function kernel (RBF) has been chosen in our work for its simplicity and its popularity in this kind of research; it is also possible to apply our method to any kernel with the same kind of parameter.