In Captain America: Civil War we see Peter Parker come home to see Tony Stark chatting with his Aunt. Later he tells Peter that he knows he's Spider-Man, and that he wants to recruit him.
How does Tony Stark know that Peter Parker is Spider-Man?
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Sign up to join this communityIn Captain America: Civil War we see Peter Parker come home to see Tony Stark chatting with his Aunt. Later he tells Peter that he knows he's Spider-Man, and that he wants to recruit him.
How does Tony Stark know that Peter Parker is Spider-Man?
In short: He is a multi-billionaire genius and has sources, but here is what the official person who worked on the film said:
And from geektyrant:
So how exactly did Stark know about Peter Parker, a.k.a. Spider-Man? During an interview with ComicBook.com Markus offered a pretty cool explanation.
"I think he's been keeping tabs. I think he might know about everybody." I imagine when he says “everybody” it also means the characters in the Netflix series like Daredevil, Jessica Jones, Luke Cage, Iron Fist and The Punisher. I mean, how can he not know about those guys, right?
He continued:
"Tony has A.I. somewhere running crime statistics. He can see where it's going up and heroes might be needed and where it's going down and there might be heroes. It's why he built Ultron in the first place."
Similar statement given on cinemablend too.
Although Ankit Sharma's answer is correct, the user Plexus asked a good question: "But how does having huge amount of info about crime, help him 'see under the mask'?" I started replying to his comment, but my reply got too long, so here goes.
The way I see it, having a huge amount of money plus advanced technology lets Tony Stark spy on people. Peter Parker had to get in and out of the Spider-Man costume, so Tony Stark would just check all his surveillance footage of Spider-Man until he could watch the costume change.
After that, he could use facial recognition to find out where this unnamed kid lives, where he goes to school, etc. Knowing that information would make it simple to narrow down which name is his (only kids who go to that school, only people who live in that apartment building, etc.). Tony also could have used lip-reading software on the friends / teachers / family around Peter: when they said Peter's name, Tony could capture it.
In a nutshell: through surveillance and possibly-fictional analytic software, Tony could figure out Peter's name and where he lives.
I believe the Answer is quite simple. It was S.H.I.E.L.D.'s (Hydra's) 'Project Insight'. S.H.I.E.L.D.'s goal was to identify and locate/neutralize terrorist threats, HYDRA's goal was to identify & locate/neutralize anyone who might work against them especially super powered individuals. It would have known about anyone with an altered DNA. I imagine whatever method they used was probably Stark technology, but regardless he had access before S.H.I.E.L.D. was disbanded, or he found out by analyzing the data agent Romanov leaked, or he hacked/accessed the technology after S.H.I.E.L.D. was disbanded, maybe when he hacked the tech when he was on board the heli carrier, no telling what Jarvis got for him when he did that. Stark could have put back doors into a lot of S.H.I.E.L.D. technology he is that kind of person.
This is what I saw in Spider-Man: Homecoming, in this movie, Tony Stark saw lots of videos of Spider-Man on internet. He used to operate in only one area. So according to Tony Stark's data for that area, only Peter Parker matched the description. So he stalked him for a while and hence confirmed that Peter Parker is a Spider Man.