How Old is Batman and Joker?

The "contemporary" age of Bruce Wayne is actually relatively easy to pinpoint. Wayne always had one age at which he stopped aging in the comic book continuity, one age that was given to him to last and be one of his defining physical characteristics. Lets start from the genesis of the character

Bob Kane mentioned in the late 1980's that he envisioned Bruce Wayne as being like young Cary Grant ( via BRT). Cary Grant was 35 in 1939 when Batman/Bruce Wayne was born creatively.

This is very much in line with Batman's age established in Modern continuity - 34.  Batman #599 states that Bruce Wayne's parents were murdered when Bruce was nine, nearly 25 years ago. That would make Bruce 34. 

One noticeable difference between the two continuities is that Modern Age I establishes that Bruce debuted as Batman at the age of 25, Year One in particular. So in contemporary timeline, Batman is purging crime from  Gotham City's streets for 9 years

IN THE MOVIES

BATMAN 

* At the time of the shoot Adam West was 38 and finished up at the age of 40, which would make him 4 years older than the comic book counterpart at the beginning of the series

BATMAN

* Michael Keaton was at the age of 38 when he was shooting the first Batman

BATMAN RETURNS

He was 41 at the time of Batman Returns

BATMAN FOREVER

* At the time of the Batman Forever shoot Val Kilmer was 36

BATMAN & ROBIN

* George Clooney was 36 at the time of the Batman & Robin shoot. It is interesting to note that at the time Clooney described Batman as being a "35 year old guy", whether it was a lucky guess or did DC supplied him with the info on the character is unknown.

BATMAN BEGINS

*At the time of the shoot for Batman Begins Bale was 30, making him the youngest actor to play the character in theatrical Batman movies, and making him 4 years younger than his comic book counterpart.

THE DARK KNIGHT

He was 34 on the shoot for The Dark Knight

THE DARK KNIGHT RISES

and 37 for The Dark Knight Rises

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JOKER

 Joker's age is never directly mentioned in the comic books. The common notion is that Joker is much older than Wayne, probably stemming from the TV show and the 1989 movie, however it seems like they're the same age. The idea of Joker being older than Batman might also come from the fact that the artwork often depicted Joker as someone looking like an aged man in late 30's or early 40's, or the idea alone that he's a gangster and a leader of mobsters in the Golden and Silver eras, something that usually seasoned, older gangsters could be. 

Let's again start with the genesis of the character. Joker's appearance was based on Conrad Veidt's character from the movie "The Man Who Laughs", which is a nice way of saying that Bob Kane simply drew the character on paper without any changes. Kane was a self proclaimed copycat and the Joker was virtually the Veidt character with green hair

Conrad Veidt was 35 in "The Man Who Laughs" and since Joker was an on-paper depiction of the character from the movie, it was therefore depiction of a 35 year old man. 

This would also more or less match the Modern Age depiction of the character. So Batman was said to start his crime fighting career at the age of 25 and Joker fell into the chemicals shortly after Batman's first appearance when he was still a gasp inducing novelty. If he's the same age that Batman is, that would make him 25 by the time he made the jump which would match the physical depiction of the character and the story - in The Killing Joke the comedian (later in continuity named Jack) is depicted as a young man who is struggling to find a job and support his pregnant wife who's expecting their first baby. So then in contemporary timeline, 9 years later, Joker would also be 34/35 and that would match the original character.

IN THE MOVIES

BATMAN

* At the time of the shoot Cesar Romero was 59 and finished up at the age of 61, which would make him 24 years older than the comic book counterpart at the beginning of the series

BATMAN

* Jack Nicholson was 52 at the time of the Batman shoot, continuing the TV shows depiction of Joker as being much older than Batman. He was 17 years older than his comic book counterpart

THE DARK KNIGHT

* Heath Ledger was 29 at the time of The Dark Knight shoot. He was 6 years younger than his comic book counterpart

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