How old is Ash Ketchum?

Answer 1

He should be 14. He was 10 when he left Pallet Town and the Pokemon League meets once a year. Ash has gone to three Pokemon Leagues and the Orange Islands series plus the Battle Frontier series are each half a year. After the Sinnoh League, Ash will become 15.

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He used to be 11, but now he's 10 - lol

EP001 - "Pokemon I choose you!"

The narrator states he is 10.

EP??? - When Ash arrives back in Viridian City for his 8th Kanto badge.

He says "It's been almost a year since we was here last." or something like that. (So he must be 11.)

BW001 - "In The Shadow of Zekrom!"

The narrator states he is 10 again.

Time travel? lol

Anyways, Ash is and will always be 10.

As he has started being a trial-goer in the Pokémon Sun And Moon saga, the Video Games states that people start island trials aged eleven, so there you go. He is either eleven or twelve.