Unlike Black Widow and Iron Man, Captain America received a happy ending in Avengers: Endgame. Cap killed two birds with six Infinity Stones by dropping off the all-powerful rocks and Thor’s hammer, Mjølnir, to their respective timelines; he then traveled to the 1940s so he could live out the rest of his life with his one true love, “Agent” Peggy Carter, as we learned when Old Man Steve Rogers appeared at the end of the film. But just how old is Old Man Steve Rogers? It’s a mystery that’s finally been solved.
In the Wired video “How Avengers: Endgame‘s Visual Effects Were Made,” Jen Underdahl, Visual Effects Producer for Marvel Entertainment, confirms that Cap is 106 years old when he tells Sam that he tried “some of that life Tony was telling me to get.”
Also, the special effects team used an actual older man.
Anyway, as a Reddit user discovered, here’s how Marvel landed on 106 years old:
Cap is born in 1920. He goes in the ice in 1945 (25 years old)
He is found in 2011 and lives on till 2023. (12 years)
This makes Cap (before he returned the stones) 37 years old.
This means he spends 69 years with Peggy. (106 – 37) Assuming he returned to Peggy in 1947, 2 years after the war ended, he would live till 2016 in alternate timeline. (2016 – 1947 = 69). 2016 is when Peggy died (in Captain America: Civil War)
This also proves that Cap returned to main timeline shortly before he time traveled for his dramatic entrance.
It sounds like Cap and Peggy had a nice life together.