The Pokémon anime that raised several generations of kids is a unique pain for people trying to piece together the backstories of characters they love.
Time hardly seems to exist in the Pokémon world.
Ash, Misty, and Brock travel through the Kanto region in an indeterminant amount of time; Ash proceeds to thoroughly explore numerous other large chunks of land without needing supplies, much rest, or anything.
He also remains youthful.
Do those traveling with Ash follow the same temporal rules as he does?
It wouldn’t make much sense if his traveling companions, and all the people of the world, didn’t exist in the same temporal space as Ask Ketchum. We will apply Ash’s aging to Misty.
Gotta catch ’em all! Gotta catch ’em all!
Misty’s Age, Life, and Pokémon
A feisty, strong girl from the Cerulean City gym, Misty is an aspiring water pokémon trainer and part-time gym leader whose prowess as a water-type trainer is worthy of respect.
In the Japanese version, she is named Kasumi, which means mist. Makes sense.
In the show, Misty accompanies Ash and Brock from the third episode onward.
How Old Is Misty from Pokemon?
From traveling with Ash Ketchum, forging her own path to mastering water-type pokémon, to reuniting with the main cast from time to time, one would think Misty has celebrated a few birthdays; one would be wrong.
As we discussed in our Ash article, the show has been running for 25 years, but the stars have definitively NOT aged by that much.
Since Ash does not age, neither can Misty. Misty is 12 years old. She is two years older than Ash and remains as such in perpetuity. The official Japanese pokémon website, which has been updated to reflect recent seasons of the anime, still lists Ash’s age as unchanged.
Do Pokémon Characters Really Never Age?
The veritable mountain of fan theories, detailed timeline following, and speculative fiction is as entertaining as it is impressive.
In spite of that, the effort is moot save for its entertainment value. Nintendo and The Pokémon Company would not have their characters age even if you offered them every Starmie in the sea.
Pokémon characters do not age, per official Japanese sources. We’re as dissatisfied with this answer as you are, but it’s the closest thing to the truth we can get when it comes to fictional worlds. What the creators say goes.
That said, the characters do appear older with the modernizing of the art style, which is exciting and misleading.
Maybe they’ll celebrate Pokémon’s 50th anniversary with a birthday party for Ash.