According to the SpongeBob Squarepants Fandom, the show's creator, Stephen Hillenburg, stated that he wanted the characters to be ageless. But over the years, different episodes of the show have given various clues and birthdates that have people wondering how old our favorite sponge is.

A couple of episodes of SpongeBob give viewers a clear image of his driver's license that has his birthday on it. In "Sleepy Time," which aired in January 2000, his birthday is listed as July 14, 1986. But this was only in one of his dreams, so it's not concrete evidence. But in another episode, “No Free Rides,” we see his license again with the same date.

Unfortunately, the other characters of the show haven't struggled to get their driver's licenses the way that SpongeBob has. So there's been no reason for them to flash a government ID for the viewers to see. But it makes sense that some of them have a perceived age. Mr. Krabs and Plankton, for example, are probably older than Squidward, Sandy, SpongeBob, and Patrick.

We do know that Mr. Krabs and Plankton have literally known each other since birth and they're the same age. In "Friend or Foe," we find out that they were born in the same hospital on the same day. They were bullied by the same kid in school and both went into business as fast food restaurant owners at the same time.

But other characters do have specific ages. On the SpongeBob Squarepants Fandom, Patrick Star, who now has his own spin-off show, is 37 years old. (His birthday is apparently August 17, 1984.) We know that Mr. Krabs' daughter Pearl is a teenager in high school, so she's probably between 16 and 18 considering that she's seen on the show driving and has gone to prom.