I came out to myself when I was about 15 or so, then I told one friend of mine when I was 17, just by chance I met my bf around then but I don't suppose he counts as someone I've come out to, lol. But due to meeting him I came out to my aunt, and then eventually my mother, but I didn't come out to anymore of my family until I was 18 and about 3000miles away from them for a year.
My mother didn't take it too well, but she's high strung anyway. She's all worried about not having any grandkids (I'm an only child) but I still want to be a parent, so I've tried reassuring her of that. My dad took it really well, which suprised me, I think the fact that he thinks my bf's a good guy helps. I didn't come out to anyone at school until we'd practically left (at prom).
I do know that if I hadn't met my bf I wouldn't have come out when I did, probably not until I got to college, I know that several of my friends here at uni have moved away from home to go to college and feel a lot...more free here, but they're not out at home for whatever reason. I agree with what everyone else has said, don't come out because you feel like you have to because you're a certain age, come out when it feels right to you, and remember, it's a gradual process, when you come out to friends etc may well be different to when you come out to your parents.