Fret Nice is a platformer with musical elements that can be played with a regular or a guitar controller. Choosing from four characters, players travel to different levels to defeat enemies and collect musical notes. Enemies need to be transformed through music and attacking can only be done while the air after a jump. Jumping is done by swinging the guitar controller neck forward, which can be remapped to a button in the options. Enemies have five different facial features that are visual cues to how to defeat them. These refer to five different notes and the pattern needs to be repeated to be successful. A single facial feature can appear multiple times to make for longer patterns. Characters can also sprint and hang in the air.
New stages are unlocked by earning medals and sometimes they will need to be replayed multiple times. Ending a level is always done by escaping with a helicopter, and while going up it is possible to shoot a few bells to create a familiar melody. Other typical elements are air streams that hold characters in the air and drums that act as trampolines. The visual style makes everything look like a paper cutout and each character can be customized extensively in the options.