Multi-rate oversampling of analog signals in storage devices is described. A method of processing an analog signal derived from a storage medium in a storage device includes: filtering the analog signal with an anti-alias filter having a fixed cut-off frequency related to a target sampling rate; sampling the analog signal using an over-sampling rate of a plurality of over-sampling rates provided by a variable-rate analog-to-digital converter (ADC) to produce an over-sampled digital signal; and filtering the over-sampled digital signal using a decimation filter of a plurality of decimation filters provided by a digital signal processor (DSP) to produce a digital signal having the target sampling rate.