How Sign in with Google actually works
A simple club analogy explains how Sign in with Google works without sharing your password, making the security model easy to grasp.
The easiest way to understand Sign in with Google is to think of a club door. You want to get in, but the door person doesn’t know you. So you go to a trusted friend — let’s call them the bouncer — and say, “Hey, you know me, right? Can you vouch for me?”
The bouncer says, “Sure,” and hands you a wristband. You go back to the door, show the wristband, and the door person checks it. Is it real? Does it have the right hologram? Through the magic of cryptography, they verify it’s legit. Since they trust the bouncer, they let you in.
The nice part? You never gave your Google password to the club. You only showed a temporary pass. So if the bouncer gets compromised, they don’t have your actual credentials to steal.