---
id: 'limits'
title: 'Realtime Limits'
description: 'Understanding Realtime limits'
sidebar_label: 'Limits'
---
Our cluster supports millions of concurrent connections and message throughput for production workloads.
Upgrade your plan to increase your limits. Without a spend cap, or on an Enterprise plan, some limits are still in place to protect budgets. All limits are configurable per project. [Contact support](/dashboard/support/new) if you need your limits increased.
## Limits by plan
| | Free | Pro | Pro (no spend cap) | Team | Enterprise |
| -------------------------------------------------------------------------------------------------- | -------- | -------- | ------------------ | -------- | ---------- |
| **Concurrent connections** | 200 | 500 | 10,000 | 10,000 | 10,000+ |
| **Messages per second** | 100 | 500 | 2,500 | 2,500 | 2,500+ |
| **Channel joins per second** | 100 | 500 | 2,500 | 2,500 | 2,500+ |
| **Channels per connection** | 100 | 100 | 100 | 100 | 100+ |
| **Presence keys per object** | 10 | 10 | 10 | 10 | 10+ |
| **Presence messages per second** | 20 | 50 | 1,000 | 1,000 | 1,000+ |
| **Presence calls per client, per 30 seconds** | 5 | 5 | 5 | 5 | 5 |
| **Broadcast payload size** | 256 KB | 3,000 KB | 3,000 KB | 3,000 KB | 3,000+ KB |
| **Postgres change payload size ([**read more**](#postgres-changes-payload-limit))** | 1,024 KB | 1,024 KB | 1,024 KB | 1,024 KB | 1,024+ KB |
| **Broadcast replay retention ([**read more**](/docs/guides/realtime/broadcast#broadcast-replay))** | 72 hours | 72 hours | 72 hours | 72 hours | 72 hours |
| **Broadcast replay messages per request** | 25 | 25 | 25 | 25 | 25 |
Beyond the Free and Pro Plan you can customize your limits by [contacting support](/dashboard/support/new).
## Limit errors
When you exceed a limit, errors will appear in the backend logs and client-side messages in the WebSocket connection.
- **Logs**: check the [Realtime logs](/dashboard/project/_/database/realtime-logs) inside your project Dashboard.
- **WebSocket errors**: Use your browser's developer tools to find the WebSocket initiation request and view individual messages.
You can use the [Realtime Inspector](https://realtime.supabase.com/inspector/new) to reproduce an error and share those connection details with Supabase support.
Some limits can cause a Channel join to be refused. Realtime will reply with one of the following WebSocket messages:
### `too_many_channels`
Too many channels currently joined for a single connection.
### `too_many_connections`
Too many total concurrent connections for a project.
### `too_many_joins`
Too many Channel joins per second.
### `tenant_events`
Connections will be disconnected if your project is generating too many messages per second. `supabase-js` will reconnect automatically when the message throughput decreases below your plan limit. An `event` is a WebSocket message delivered to, or sent from a client.
## Postgres changes payload limit
When this limit is reached, the `new` and `old` record payloads only include the fields with a value size of less than or equal to 64 bytes.