There is no maximum age limit to play in the FIFA World Cup, and the tournament is generally for senior professional players, not kids. FIFA rules and recent explainers say players can be selected as long as they meet eligibility and team selection requirements, while youth players usually compete in Under-17 or Under-20 competitions instead.

What that means

  • You do not need to be a certain age like 18 or 21 to play in the World Cup.
  • There is also no official upper age cutoff.
  • In practice, a player must be good enough, fit enough, and eligible to represent their country.

Simple example

A 16- or 17-year-old can be called up if they are already a senior-level player, while many teenagers instead play in FIFA youth World Cups first.

One note

Some sources mention a minimum age for FIFA senior competitions, but the clearest takeaway for the FIFA World Cup itself is that there is no fixed age limit in the way people usually mean it.

If you want, I can also explain the difference between the FIFA World Cup, U-17 World Cup, and U-20 World Cup.