While Bruce Wayne’s origin has been retold countless times across comics, movies, TV shows, video games, and more, one of the most highly regarded tellings of the Caped Crusader’s beginnings would be 1987’s “Batman: Year One,” which also gives us some concrete numbers. In this story from writer Frank Miller and artist David Mazzucchelli, Bruce Wayne returns to Gotham at age 25 after twelve years of training abroad. In the comic, Bruce recollects that his parents were killed 18 years ago, which would have made him seven when he watched them gunned down.
But this Batman is only just learning the ropes and is still blundering in his early attempts at heroism. The rookie Batman of “Year One” is a far cry from the ready-for-anything Dark Knight that we’re more accustomed to. While this origin story may not be canonical for every continuity making up DC’s sprawling multiverse, it at least gives us a good idea of how old Bruce would have had to have been when he started his career as Batman.