EventBridge Cost Calculator
Price EventBridge custom events, Scheduler invocations, Pipes requests and archives, with 64 KB event chunk billing.
About EventBridge Cost Calculator
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.
Formulas
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.
- billed event unit
- One published event of up to 64 KB
- target
- A rule destination — matching and delivery add no charge
- archive
- Optional durable copy of events, priced per GB stored for replay
Fan-out to targets
target deliveries = events × targets matched, which is free on EventBridge but bills on whatever the target is.
Worked example
With the default values below, EventBridge Cost Calculator returns Estimated Monthly Cost of $11.25. Change any input above and every figure here is recalculated in your browser.
Inputs used
- Custom events published per monthminimum 0 events
- 10,000,000 events
- Average event sizeaccepts 0.1–256 KB
- 2 KB
- Targets matched per eventaccepts 0–20 targets
- 2 targets
- Scheduler invocations per monthminimum 0 invocations
- 1,000,000 invocations
- Pipes requests per monthminimum 0 requests
- 0 requests
- Archive events for replay
- No
- Price per million custom eventsminimum 0 USD
- 1 USD
- Scheduler price per million invocationsminimum 0 USD
- 1.25 USD
- Pipes price per million requestsminimum 0 USD
- 0.4 USD
- Archive price per GBminimum 0 USD
- 0.1 USD
Results
- Estimated Monthly Cost
- $11.25
- Custom Event Cost
- $10.00
- Scheduler Cost
- $1.25
- Pipes Cost
- $0.00
- Archive Cost
- $0.00
- Billed Event Units
- 10,000,000
- Target Deliveries per Month
- 20,000,000
Step by step
- 1Values used
- 2EventBridge Cost
- 3Fan-out to targets
- 4Estimated Monthly Cost= 11.25
- 5Custom Event Cost= 10.00
- 6Scheduler Cost= 1.25
- 7Pipes Cost= 0.00
- 8Archive Cost= 0.00
- 9Billed Event Units= 10,000,000
Assumptions and limits
- The result is derived only from the 10 inputs listed above. Anything not among them is not part of the calculation.
- In particular, this calculator does not take inflation, tax or compounding frequency into account.
- Figures are rounded for display to 2 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.
Frequently Asked Questions
How is EventBridge Cost calculated?
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.
Why does EventBridge Cost matter?
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.
What values do I need to enter?
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.
Are events from AWS services charged?
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.