How old are the characters in Birth by Sleep?

[Sakulily]

I assume Ventus is 15, as like Lea and Isa.
Terra around early 20s, and Aqua around 19 - early 20s.

 

[odessa]

I put Aqua as slightly younger than Terra, and Lea slightly younger than Isa. Ven strikes me as younger than Lea though (only because of the blatant Roxas and Axel connotations there).

 

[Shadowrelm 150]

Terra: 19 - Nomura has said Xemnas looks to be at the age of 30 in Kingdom Hearts 2.
Aqua: 18 (probably 19).
Ven: 14 - BBS takes place 10 years before KH1. Sora was four in BBS. He was just born when he connected hearts with Ven, making Ven 10 in that scene. Therefore Ven is 14 in the game (from the tutorial).
Lea and Isa: Probably the same age as Ven, if not, 15.
Earqus: 40-50
Master Xehanort: 55+
Vanitus: Body wise he is 14, same age as Ven. But from creation he is only 4.