According to Amazing Spider-Man (vol. 3) #1, published in April 2014, Peter was bitten by the spider 13 years ago, and it was previously established he was around 15 at the time. He is likely now nearing his thirties.
The Marvel Cinematic Universe Spider-Man is a different case. but first…
SPOILER WARNING! (For Avengers INFINITY WAR and ENDGAME).
Spider-Man was still in high school when the “snapture” occured, making him around 16 years old. He returned as he was five years later, making him biologically 16 years old, approximately, though it would be 21 years from his birth (established as August 10, 2001). As of writing this, the Marvel Cinematic Universe Wiki has this definition for Peter Parker’s age.
***OLD ARCHIVE POST***
Peter Parker is 28 years old in the 616 Marvel Universe.
This answer is subject to change, as writers may adapt the age through their stories. Peter’s age is somewhat fluid, aging in real time at some points, while almost not aging at all for some periods.
For those looking for the previous response, we’ve maintained it below:
How Old Is Peter Parker?
The short answer: 28
Spider-Man/Peter Parker has been around for ages. Spider-Man was first launched in 1962 under an aura of uniqueness, being one of the only superheroes to be a teenager, a role until then only occupied by sidekicks. But exactly how old is Peter Parker?
How Old Is Peter Parker in the Core Titles?
In the core Spider-Man universe still currently published around the title Amazing Spider-Man, Peter Parker was 17 when first introduced in 1962. Using 2011 as a benchmark, simply adding the years in between would make him 66! Don’t panic, though, because Marvel has a rule of thumb concerning the passage of time in their comics. First, Marvel loosely employs a three-to-one ratio of passage of time, meaning roughly one year passes in the comics every three publication years. Second, they employ what is a called a “sliding Timescale”, or “Floating Timeline”, which generally means that as the years pass, events referenced in the real world are relative to the time of publication. For example, Spider-Man may reference pop culture of the 90’s (90210 anyone?), or you might hear MJ say “This is the 90’s!”, yet, in 2011, these events only occurred 5 years ago. Other important things, like real life wars referenced in one era of comics being retconned to a more recent conflict to maintain the passage of time, which is more important that it occurred more recently that the particular events of that conflict. So how old is Peter Parker considering these facts?
Calculating How Old Is Peter
Well, if Peter Parker was 17 in 1962, and using 2011 as a benchmark, that would mean 49 publications years have passed. Using the three-to-one rule, that would mean roughly 16 years have passed, making him currently 33 years old.
To verify, we’ll benchmark against stated ages in published issues. In an issue of Spectacular Spider-Man in 1997, Flash Thompson, considered to be the same age as Peter Parker, states that he is 25. In 1997, 35 publication years would have passed, meaning roughly 12 years had passed, making him actually 27. To adjust, we can consider that since there is such a large gap (9 months-ish) between Spider-Man’s introduction and the launch of the Amazing Spider-Man in 1963. Using 1963 as a base year, that means he would be more likely 11 years would have passed, and, if Flash’s birthday is later in the year, then he would effectively be 25.
So, how old is Peter Parker, really? This change in year would mean Peter Parker is more likely around 32 years old in 2011.