Enter a @username or t.me link — we'll show the numeric ID, what it is (person, bot, channel or group) and what the profile shows. For people and bots, also the approximate sign-up date.
The Braidix parser collects members and active authors from chats and channels — with IDs, usernames and signs of a live account.
A username can be changed or sold, but the numeric ID stays with the account forever. Bots and services use it to recognise a person even after a rename, and the ID number hints at when the account was registered: older accounts are less likely to be bots.
Channel and supergroup IDs start with -100 — that's the format the Bot API and most services expect.