A rate adjustment apparatus includes a first calculating section that calculates a first parameter for calculating judgment values used for judging whether puncturing or repetition is to be performed with respect to individual bits of input data, a second calculating section that sequentially calculates a second parameter for each of a plurality of processing units into which input data is divided, by computation using a recurrence equation obtained from a relationship between the judgment values corresponding to two processing units of the plurality of processing units, and an executing section that obtains the judgment values with respect to individual bits forming each of the processing units by using the first parameter and the second parameter respectively calculated by the first calculating section and the second calculating section, and executes deletion or addition of bits based on the obtained judgment values.