Mordecai and Rigby are both 23 years old at the start of Regular Show, as stated in the first episode.

Quick Scoop

  • In the episode “The Power,” Mordecai explicitly says that he and Rigby are 23.
  • Fans generally agree that they stay in their early-to-late twenties through most of the series.
  • By the time of the series finale and the big space arc, fan timelines usually place them around 28–29 years old, depending on how you count the “time in space” years.

Many forum discussions break it down as: 23 at the beginning, about 29 by the final battle, with some debate about whether extra “space years” actually count for their real ages.

At a high level: canon gives one clear number (23 at the start), and the rest is pieced together by fans using episode events and dialogue.

TL;DR: Mordecai and Rigby are canonically 23 at the beginning of Regular Show; fan math places them close to 29 by the end.

Information gathered from public forums or data available on the internet and portrayed here.