Originally Posted by
bat39
I see him as being at least 30, and most likely a couple of years older.
A lot of rationales have been provided here for why Peter would logically be over 30 by now. I propose another one - ''Marvel Time''. The concept that every 4 years in real-world time roughly approximates to 1 year in-universe.
Of course, in the early years, the Marvel Universe operated in something approximating real-time. For instance, Peter went from being a 15 year old high-schooler in 1962 to an 18 year old college freshman in 1965. Ergo, Marvel Time kicks in for Spider-Man around 1965, when he enrolls in college. It's been 56-57 years since then in real-life, which translates to 14 years in Marvel Time. And Peter was Spider-Man for 3 years before that...meaning he's been Spidey for 17 years in total, making him 32 now.
The time compression also works pretty well when you consider many of Peter's personal and professional milestones across the decades.
1. He graduates college in 1978 (i.e. 13 years since he was a college freshman, a little over 3 years in Marvel Time), making him 21. Okay, it should actually be 22 (it's not a perfect model!), but still, close enough.
2. He gets married in 1987 (i.e. 22 years since he was a college freshman, a little over 5 years in Marvel Time), making him 23. Which is plausible enough.
3. He becomes a high school teacher in 2001 (i.e. 36 years since he was a college freshman, 9 years in Marvel Time), making him 27. Which makes sense.
4. He (or rather Ock posing as him, but still) founds Parker Industries in 2013 (i.e. 48 years since he was a college freshman, 12 years in Marvel Time), making him 30. Again, makes sense.
And in-universe, it's been 2 years since then (since it's been over 8 years in real-life).