If you’re looking for a channel to join, all you have to do is visit the Chat Rooms page here on the site. The automatically generated page lists channels, their topics, and the number of users currently in the channel, listed from the channel with the most users to the channel with the fewest users.

To get your channel to show up on the list:

• Make sure that your channel is not set to +s (secret) or +p (private). Private or secret channels do now show up on the list.
• Maintain more than 5 people in the channel. The list is limited to channels with 6 or more users.

That’s it. If you have a public channel with 6 or more users, it will show up in the official list on the website. The channel doesn’t have to be registered, but we always recommend that you register your channel. It’s free and gives you better control over your chat room.

How do you determine if your channel is public?

Just use the command:

/mode #channel 

For example: /mode #topgear. In your status window, you’ll see something like this:

Mode for room #topgear is "+ntrS"

The Channel Modes page will help you decipher that response, but for our purposes, notice that there is no “s” and no “p.” That means the channel is neither secret nor private. Note that case matters. The channel #topgear is +S (strips color codes), but not +s (secret).

—posted by Tengrrl/Bunny