How old is Derek actually?

Where there are msny ways to see how old he realy is but we can not ever know how old he is onless he conmes and talks to us.YOU ROCK DO U HAVE A GIRL FRIEND

My guess is 26 years old

hes 24 it says he was born in 88

He's 24 how can u still sexy at that age

In the 3 seasons it's been almost 1,5 years. in the first season although stiles says that Derek went to the same school, it doesn't mean that they where all together at the same time. There must be other high schools he could have attended, but he went to their high school. And Peter was 6 years like that (comatose-like) but the fogo was 10 years before the 1st season. Derek was 15 when he met paige... probably around 18 when he met Kate and the fogo happend. So around 28 in the first season?? Plus in the flash back Peter was too young to be that old now in the present...

He's approximately 24 in the first season, so now (post S5) he's about 26.

(This is mostly guesstimation, with a bit of calculating due to his age in flashbacks, I don't think Jeff even knows, honestly. xp)