A storage device includes a non-volatile memory including a plurality of blocks, a buffer memory that stores a plurality of on-cell counts, which are generated by reading memory cells connected to a plurality of reference word lines of the plurality of blocks by using a read level, and an artificial neural network model, and a controller that inputs an on-cell count corresponding to a target block among the plurality of on-cell counts and a number of a target word line of the target block to the artificial neural network model, and infers a plurality of read levels for reading data of memory cells connected to the target word line using the artificial neural network model.