An equalizer includes a sampler configured to sample an edge and data of an input signal or an induced signal obtained from the input signal, a clock generator configured to generate an edge clock used to decide sampling timing of the edge and a data clock used to decide sampling timing of the data based on the sampled edge and the sampled data, and a controller configured to control the sampling timing of the edge and the sampling timing of the data based on the sampled edge and the sampled data.