How Do You Find a Telegram Channel, Group or User ID?

First: you probably do not need it

Setting up forwarding with Phantom Forwarder does not involve identifiers. You connect your Telegram account, then choose the source and the destination from a list of your own chats, by name, and the identifier is stored for you underneath. That matters beyond convenience: a chat picked from the list cannot be the wrong one, whereas a number typed by hand very easily can be.

The rest of this page is for the cases where you genuinely need the number: comparing two chats with the same name, describing a chat precisely in a support request, or working with something else that asks for it.

Reading the ID from Telegram Web

This is the quickest route and it involves nothing beyond the official web client. Note that the two versions of Telegram Web format the address slightly differently; the number itself is the same in both.

1. Open web.telegram.org in a browser and sign in.
2. Open the chat you are interested in.
3. Look at the address bar. The part after the # is the identifier of that chat.
4. A group or channel appears with a minus sign in front, for example -1001234567890. A person appears as a plain positive number.

What the -100 prefix means

Channels and supergroups are shown with a -100 prefix in front of their internal number: an internal 1234567890 becomes -1001234567890. Ordinary small groups use a plain negative number without the 100. It looks like a quirk and it is: what matters in practice is that you copy the whole thing, minus sign included, and that you do not add or remove the prefix by hand.

One consequence catches people out: when a small group is upgraded to a supergroup, its identifier changes. Anything pointing at the old number stops matching, and the fix is to point it at the group again.

Forwarding a message to find the origin

If you need to identify the chat a message came from rather than the chat you are in, forward the message somewhere you control and inspect it there. The forward header carries the origin, unless the original chat has forwarding restrictions enabled, in which case there is nothing to inspect and you have to open the chat itself.

Forum Topics: a group with rooms

In a group with Topics enabled, each room behaves like a separate chat, and pointing at the group is not the same as pointing at a room inside it. In Telegram Web, opening a topic adds a second number to the address: the group, then the topic. The General room counts as a topic too, which is the detail that most often causes a rule to watch the wrong thing.

Here again, choosing from a list avoids the whole problem: the room appears by name, under its group.

A word on identifier lookup services

There are third-party services that report the identifier of any chat you point them at. They work, and we are not going to pretend otherwise, but you are handing a stranger a piece of information about where you spend your time. For the two minutes it saves over reading the address bar, it is not a trade we would make, and it is certainly not one to make with a work account.