I’d say 11-12 is spot on.

I don’t think they have official ages, I’m not sure.
 
Also, seeing how the show is nearly 5 years old, unsurprisingly the CMCs voices are no longer even “kids,” and are all teenagers now.  
They still do good voices though. (It’s easier for girls to sound young then guys.) I’d be sad if they replaced them, and they still seem to enjoy doing the show. Clair “Sweetie Belle” Corlett said even if she didn’t voice for the show, she’d still be a pegasister, she likes it so much now. It’s nice to see even those working on it enjoy the show to.

I saw her as a young 8-10 year old in the first two seasons but by season 3 and 4 she behaves more like a 12-15 year old.

@Background Pony #E3F1  
Original intention was 7.  
Eh, who knows what the ages of the characters are?

Apple Bloom is surprised at her sudden age progression.

Is Apple Bloom REALLY 12 years old btw  
I’d give her 9-10 years top