How old is Ezio in Assassins Creed Revalations

he's around his late 40's,if you read the book (which includes Assassin's Creed: Embers) it will tell you that he and Sofia celebrated his 50th birthday so it has led me to believe that AC:R take place around when he is 45-49 and that he turns 50 some months after he and Sofia get entrance to Altair's library.