A method of operating a storage controller includes receiving raw data indicating a series of bits each corresponding to one of threshold voltage states, performing a first state shaping for reducing a number of first target bits of the series of bits, logical values of the first target bits being equal to a logical value of a target threshold voltage state of the threshold voltage states in a first page of plural pages, generating first indicator data that indicates the first target bits based on the first state shaping, compressing the first indicator data, and storing the compressed first indicator data.