A printer includes a feeding portion configured to feed a printing medium, a printing portion including a plurality of heating elements configured to perform printing of one line at a time on the printing medium, and a processor configured to specify numbers of ON dots for at least a first specified block and a second specified block, specify first speeds that respectively correspond to at least the first specified block and the second specified block based on the numbers of ON dots, set a second speed for the second specified block based on the first speeds that respectively correspond to the first specified block and the second specified block, such that the printing medium is fed at the first speed for the first specified block when the printing of the first specified block is performed, and control the feeding portion and the printing portion.