Superman is widely regarded as one of the first comic book superheroes, helping to popularize the genre as a whole, but one mystery that readers have never quite been able to solve is his age. While Superman comics have been around for over 80 years, just how old is the Man of Steel himself within the DC universe? The answer is… it depends.

Determining the age of Superman is especially challenging given how many different versions of the character have existed over the years. Depending on the storyline, Superman may be just starting his career as a hero (Superman for All Seasons) or be returning after years of retirement (Kingdom Come). In any case, most storylines generally depict Superman as either young, old, or in his prime while never explicitly stating his age. However, piecing together context clues across various comics can bring us closer to an exact number. For example, in an advertisement for an old Lois Lane comic, Lois’ age is revealed to be 22. Since Superboy #90 shows Lois and Clark to have been in high school at the same time, the Big Blue Boy Scout would logically also have to be somewhere in his 20s, likely a little older than Lois. That works for the old-school Action Comics, but what about more recent series?

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Superman: American Alien #1 by Max Landis states that the Man of Steel first arrived on Earth on April 18th, but, unfortunately, this doesn’t do us much good without a corresponding year. However, two issues later, Clark accidentally winds up on Bruce Wayne’s yacht during the millionaire’s 21st birthday party. The catch is that everyone thinks Clark is Bruce since Bruce isn’t actually there (he’s off training with the League of Assassins). Regardless, it’s safe to say that Clark is also around 21 at this time. Then, in issue #4, the story flashes forward a few years to when Clark is working at the Daily Planet in Metropolis, but has yet to make his debut as Superman. However, within that time, Bruce has returned to Gotham and already begun his career as Batman, which subsequently inspires Clark to become a costumed hero in the next issue. Since the usual timeframe of Bruce’s training with the League of Assassins is around 10 years, and he was already partway through it in issue #3, we can assume Clark is a little younger than 30 when he first became Superman - at least, in this storyline.

The New 52 was a revamping of the entire DC Universe that saw most of the heroes get a few years shaved off. While no explicit ages are given here, it’s implied that Clark Kent gets hired at the Daily Planet right out of college, which would place him in his early 20s when he first dons the cape. However, this version of the Man of Steel later merged with the Rebirth Superman, who was old enough to be married and have a child, leaving the new Superman with an ambiguous age. Assuming that the age is an average of the two versions, he’s likely around 30 here, as well.

The closest we ever get to an exact birthdate for Superman comes in the World of Krypton limited series from 1979, which focuses on Superman’s father, Jor-El, in the years before the planet’s destruction. World of Krypton #2 gives an exact date for Kal-El’s birth - but don’t get too excited - the date provided uses Kryptonian measurements of time, so Superman’s date of birth is written as 38 Eorx 9998. Since Krypton has a different number of days in a week and months in a year, mathematically translating this number into Earth measurements of time would result in Superman having a different birthday every year. This could actually explain why there are so many different answers as to what Clark's birthday is. Some sources say its February 29, which reportedly began as a joke to explain why Superman stays eternally youthful (he was born on Leap Day, so he only ages every four years). Others say it’s June 18, the same as the birthday of Bud Collyer, the voice actor who played Superman on the radio in the 1940s.

The unfortunate truth is that Superman’s history is filled with contradicting information that makes it virtually impossible to assign him an actual age, which makes sense given that the Man of Steel is meant to stand the test of time. All in all, most would agree that Superman is perpetually somewhere between his mid-20s and mid-30s, but seeing as he is essentially immortal, his age is practically irrelevant, anyway.

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