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Part 6 of 7 · Uptime status poster series ~5 min read

What the uptime status poster costs

Checking four journeys from three regions every minute is about five hundred thousand invocations a month, which sounds enormous and costs very little because each one is short. Here is where each cent goes.

Key takeaways

  • About $1511 a month at 8 journeys, 3 regions. Roughly $3021 at 8 journeys, 6 regions.
  • One Bedrock read per check is the only line that scales. Everything else is rounding.
  • Nothing is always-on, so a quiet month genuinely costs almost nothing.
  • Half a million short invocations a month is a few dollars. Frequency is cheap; journey count is what costs.
  • The duplicate test runs before the read, so resends are free.
  • The three real risks: a retry loop, storage nobody expires, and a bigger model than the job needs.

The bill at three volumes

These are US East prices at the time of writing, at three volumes that bracket most small businesses. Find the bar closest to your own and read across.

Monthly cost of the uptime status poster at three volumesA stacked bar chart with three bars, one per volume tier: 4 journeys, 3 regions totalling about $756, 8 journeys, 3 regions totalling about $1511, and 8 journeys, 6 regions totalling about $3021. Each bar is stacked from bands. The largest and fastest-growing is Bedrock, one read per check, in teal. Then SES for the messages, in pink. Then S3 and DynamoDB storage in green. Then a fixed orange band for Secrets Manager and AWS Budgets, which is eighty-six cents at every volume. Then a grey band for Lambda, SQS and CloudWatch. A note says the read is the only bar that grows with the business and the orange band never moves.$0$1000$2000$3000$4000~$756.244 journeys, 3 regions~$1511.248 journeys, 3 regions~$3021.248 journeys, 6 regionsBedrock — one read per checkSES — asks, results, receiptsS3 + DynamoDBFixed — Secrets Manager, BudgetsLambda, SQS, CloudWatchThe read is the only bar that grows with the business. The orange fixed band never moves.
Fig 1. The monthly bill at three volumes. The teal band — one model read per check — is the only part that grows; the orange fixed band is the same 86 cents at every volume.

Line by line

LineAt 8 journeys, 3 regionsHow it scales
Bedrock read$0.00Linear. One call per check, roughly 1,800 in and 200 out tokens.
SES$500.00Linear. About 2e-05 messages per check.
DynamoDB + S3$160.28Storage grows with what you retain, not with throughput.
Lambda + SQS$0.12Linear, and effectively free at this scale.
CloudWatch$0.16Flat, if you set retention. Unbounded if you do not.
Secrets Manager$0.40Flat. One secret, $0.40 a month.
AWS Budgets$0.46Flat. Two actions, so you find out before the bill does.

Each check is an HTTP sequence rather than a browser load, which is what keeps this affordable at a one-minute interval. There is no model anywhere in the system.

The three ways this bill surprises you

Every one of these has happened to somebody, and all three are cheap to prevent.

  • Checking every thirty seconds. Doubles the bill for a detection improvement smaller than the two-round confirmation delay already imposes. A minute is the right interval.
  • Full page loads instead of HTTP requests. A headless browser per check is the page speed watcher’s cost profile applied to something running every minute, which is a hundred times the bill for no additional signal.
  • Log retention left at never. Half a million invocations a month with default logging is by far the largest line on this bill within weeks.

What it costs when nothing happens

This matters more than the headline number for a seasonal business. In a month with nothing to process the bill is the fixed band: Secrets Manager at forty cents, AWS Budgets at forty-six, and a few cents of storage. Call it a dollar. There is no instance to stop and nothing to remember to turn off.

The monthly bill at four volumes plus one failure modeA horizontal row of five boxes. Quiet month, about one dollar. 4 journeys, 3 regions, about $756. 8 journeys, 3 regions, about $1511. 8 journeys, 6 regions, about $3021. And one bad retry loop, about two hundred dollars. A note says four of these are the design working and the fifth is a missing dead-letter queue.THE BILL, AT A GLANCEQuiet month~$14 journeys, 3 regions~$7568 journeys, 3 regions~$15118 journeys, 6 regions~$3021One bad loop~$200Four of these are the design working. The fifth is a missing dead-letter queue.
Fig 2. The bill at a glance, including the one that is not a volume at all. A retry loop with no dead-letter queue costs more than every legitimate use of the system put together.
  • Management
  • Analytics
  • Front-end & mobile

Set these on day one

  • A dead-letter queue on every SQS queue, with a maximum receive count of three.
  • Thirty-day retention on every CloudWatch log group. There is no default that is safe.
  • An S3 lifecycle rule on the object prefix, tiering at 90 days and expiring at your actual record-keeping horizon.
  • Two AWS Budgets actions — one that emails at half your expected spend, one at double it. The second is how you find out about a loop in an hour instead of a month.
  • Provisioned concurrency: none. Nothing here is latency-sensitive enough to justify paying for a warm function.

Next: the same system drawn for engineers — service names, resource identifiers, IAM scopes, table schemas and the model id.

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