Price EventBridge custom events, Scheduler invocations, Pipes requests and archives, with 64 KB event chunk billing.
EventBridge charges the publisher per 64 KB event and then delivers to every matching rule target at no extra charge, which makes wide fan-out unusually cheap compared with a queue-per-consumer design. Events from AWS services onto the default bus are free; only custom and partner events are billed, and Scheduler and Pipes are separate meters at their own rates. Confirm the current per-million prices for your region before relying on this estimate. Because target delivery is free, the honest cost driver is event volume and size — teams that wrap each event in a verbose envelope can push a 60 KB payload over the 64 KB line and silently double their bill.
EventBridge Cost
billed event units = events × ceil(event size KB ÷ 64); cost = units ÷ 1 M × event price + scheduler invocations ÷ 1 M × scheduler price + pipes requests ÷ 1 M × pipes price + archived GB × archive price.
Fan-out to targets
target deliveries = events × targets matched, which is free on EventBridge but bills on whatever the target is.
billed event units = events × ceil(event size KB ÷ 64); cost = units ÷ 1 M × event price + scheduler invocations ÷ 1 M × scheduler price + pipes requests ÷ 1 M × pipes price + archived GB × archive price. EventBridge charges the publisher per 64 KB event and then delivers to every matching rule target at no extra charge, which makes wide fan-out unusually cheap compared with a queue-per-consumer design. Events from AWS services onto the default bus are free; only custom and partner events are billed, and Scheduler and Pipes are separate meters at their own rates. Confirm the current per-million prices for your region before relying on this estimate.
Because target delivery is free, the honest cost driver is event volume and size — teams that wrap each event in a verbose envelope can push a 60 KB payload over the 64 KB line and silently double their bill.
This calculator takes 10 inputs: Custom events published per month, Average event size, Targets matched per event, Scheduler invocations per month, Pipes requests per month, Archive events for replay, Price per million custom events, Scheduler price per million invocations, Pipes price per million requests, Archive price per GB. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.
No. Events that AWS services publish to the default event bus are free, as are the rules that match them. You pay for custom events you put on a bus yourself, partner events, cross-region replication, archive storage and replays.