Public channels

The simplest channel type. Anyone with your public key can subscribe — no authorization callback, no signing.

When to use

• Live tickers, scoreboards, leaderboards
• Public chat rooms
• Status pages, “X people are watching” counters
• Anything where the data is already on a public web page

When NOT to use

• Anything user-specific (use private-)
• Anything with sensitive content (use private-encrypted-)

Naming

Channel names can contain [A-Za-z0-9_\-=@,.;:] and must not start with private- or presence-. Examples:

• chat
• room.42
• metrics:cpu

Subscribe (client)

const channel = pusher.subscribe('chat');
channel.bind('message', (data) => console.log(data));

Trigger (server)

await pusher.trigger('chat', 'message', { text: 'hi' });

Limits

• Max channel name length: 200 chars
• Max event name length: 200 chars
• Max payload size per event: 100 KB
• Max channels per single trigger call: 100 (for fan-out to many channels)