After the info in the link below was written, the slow ratings were given a boost by chess.com staff, so this isn't as reliable, but maybe it will help you a little at least.
http://www.chess.com/article/view/chesscom-rating-comparisons
The best way to estimate your FIDE rating is to play in FIDE events or at a club with FIDE rated players who can play you and give you an estimate.
Websites and some programs that give ratings aren't very reliable. But at least you can compare yourself with others on this site. After a game check if they give their FIDE rating in their profile, that can help a little too. (It's not perfect because some people play with distractions or even might cheat which they don't do in FIDE tournaments.)
Hello,
I'm a begginner chess player, I play only on Chess.com. my rating in slow chess is 1416 right now. but I've been wondering weather this rating is real, and what my official rating would be considering this?