Free
US$0
- 1M message operations per period
- 20 requests/sec and 100 concurrent connections
- 5 topics with 2 partitions each
- 3-day message retention
- Webhook, retries, DLQ, replay, and MCP included
Transparent operations pricing
Start free. Scale for US$19.
Free and Paid both include SSE, WebSocket, Webhook, retries, dead-letter, and MCP. They differ in quota, throughput, connections, topics, and retention.
Plans
Two plans. The same core capabilities.
Free fits evaluation and small projects. Paid raises capacity and retention to 30 days. Both are public beta plans without an SLA.
Paid
US$19 /month
- 6M message operations per period
- 2,000 requests/sec and 500 concurrent connections
- 1,000 topics with 64 partitions each
- 30-day message retention
- Hosted functions and a higher key limit
How billing works
Operations are not just published messages.
Each 16 KiB is one size unit. A successful publish counts once, then every billable delivery counts once. Deliveries include SSE, WebSocket, HTTP long-poll, and successful Webhooks.
operations = size units × (1 publish + every delivery)
Calculate payload size
1–16 KiB is 1 unit, 16–32 KiB is 2, always rounded up.
Add fanout
A message under 16 KiB published once and delivered to 10 receivers costs 11 operations.
Model your workload
The calculator separates logical messages, deliveries, and billable operations so fanout stays visible.
History queries, DLQ reads, and management calls do not currently count. Billing is based on successful publishes and billable deliveries.
Overage and limits
No surprise usage bill.
01
Capped by default
When the included quota runs out, new publishes stop by default. Reads remain available within retention.
02
Top up, then opt in
Free and Paid can use prepaid balance. Overage continues only when the balance is positive and you enable it.
03
One overage rate
Overage is US$3 per 1M operations, deducted from prepaid balance. It stops when the balance reaches zero.
Keep reading
Estimate usage, then choose a delivery path.
Run the numbers for a real workload.
The calculator needs no login and creates no bill.