At a glance
Active Realtime Channels is the number of open Supabase Realtime channels right now. A channel is a named topic that clients subscribe to for live updates, whether that is Postgres Changes streaming row-level events, Broadcast relaying low-latency messages, or Presence tracking who is online. This card measures topic-level fan-out: how many distinct live conversations your project is currently hosting.It is the structural companion to connected-client count: many channels with few clients each, or few channels with many subscribers, behave very differently under load. A sudden climb usually means an application change in subscription behaviour rather than user growth.
What it tracks
The card reports the count of Active Realtime Channels for the selected period, sampled in real time (RT). It counts open channels (topics) on the Realtime service, distinct from the number of WebSocket clients connected to them, which is covered by Realtime Connected Clients. There is no alert threshold on this card (-); it is a capacity and behaviour signal best read against the connected-client and disconnect-rate siblings. Roles: engineering, operations.