How old are Sam and Dean Winchester at the beginning and end of their Supernatural story? Premiering in 2005, it's been quite a ride for the Winchester brothers and, by extension, Jared Padalecki and Jensen Ackles. Supernatural's debut season saw a fresh-faced Sam and Dean reunite to track down their father, hunting an eclectic selection of monsters along the way. After fulfilling Eric Kripke's initial Supernatural arc with season 5, the Winchester brothers continued to save people and hunt things, facing Leviathans, parallel worlds, archangels and, finally, God himself.

Over the past 15 seasons, Sam and Dean Winchester have matured in front of the audience's eyes, growing and adapting their roles accordingly. For example, where Dean was once the promiscuous ladies' man of the duo, he's now more interested in being a good mentor figure to Jack, the nephilim son of Lucifer. The bookish, intelligent Sam was always more of an old soul compared to his wild brother, but he too has softened over the years, letting go of the angst that once defined his character. Supernatural's Winchesters have both aged in a distinctly un-supernatural, organic way, but how old are they in season 1, and then in the final, fifteenth season?

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John and Mary Winchester welcomed Dean to the world in January 1979, and Sam arrived four years later in May 1983. Supernatural's pilot episode aired in September 2005 and takes place in a contemporary setting. This puts Dean at 26 years of age when Supernatural begins, while Sam is 22. These ages fit the narrative, as Sam Winchester is at Stanford University when Supernatural begins, but mentions applying to a law school. By comparison, both actors are a year older than their on-screen counterparts, with Jensen born in 1978 and Jared in 1982.

Jared-Padalecki-as-Sam-Winchester-and-Jensen-Ackles-as-Dean-in-Supernatural

From there, Supernatural's timeline is much more complex, with some seasons utilizing time jumps, and others blending directly from one to the next, ignoring time passed in the real world. Generally, however, Supernatural retains its modern-day setting by keeping the amount of time between each hunt relatively vague. This allows the series to catch up whenever the narrative begins to lag behind reality. Donald Trump, of all people, is useful for pinning down Supernatural to the modern era. In season 14's "Moriah," a news report references the Mueller report, which was released the same month the episode aired. Supernatural season 15 picks up in the immediate aftermath of "Moriah," but by "The Trap," has caught up to 2020, once again bringing the story in line with the real world. Supernatural's most recent episode was aired, and therefore also set, in March 2020, which would make Dean 41-years-old and Sam 36 years old (almost 37).

Adding an interesting wrinkle to Sam and Dean's ages is the amount of time they've spent dead or otherwise connected to the afterlife. Dean spent 4 months in hell after being eaten by Hellhounds and a year in purgatory with Benny, while Sam's soul was in The Cage for a little over 12 months. Although Supernatural has never explicitly stated either way, it seems unlikely that the Winchesters would continue to age in these scenarios, Dean especially. This could shave years off both brothers, technically putting Dean at 39 and Sam (or his soul at least) around 35. There are perks to the hunting life after all!

While Sam and Dean Winchester's ages aren't necessary pertinent to their current battle against God, the period of their lives Supernatural covers helps explain why the show remains so popular. Sam and Dean have been the core of Supernatural since the very beginning, and watching the brothers grow during their prime years has kept audiences coming back for more even during the weaker seasons. As mentioned previously, Sam and Dean's advancing years have informed subtle changes to both characters, ensuring the Winchester brothers remain believable in a distinctly unbelievable world.

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Supernatural season 15 returns October 8th on The CW.