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Lab 06 · Cost reveal

What does running this site actually cost? Click reveal — a Lambda calls Cost Explorer's GetCostAndUsage for the demo account's MTD spend, broken down by service. The cost-summary + free-tier panes on the right show the same thing live, with budget context.

Show me the bill

GET /api/lab/cost — calls ce:GetCostAndUsage with a MONTHLY granularity grouped by SERVICE. CE data lags ~24h so very-recent activity won't show, but the monthly total is accurate.

Click reveal to fetch the demo account's MTD spend.

Live · Cost Summary

Live · AWS Free Tier

What just happened?

Cost Explorer: CE aggregates billing data into queryable buckets. GetCostAndUsage is the bulk read API; charged at $0.01 per query so the Lambda caches its result for 15 minutes.
The numbers: The site running for one full month at expected traffic costs ~$6 — almost all of it is the WAF Web ACL + rules. Lambda + API Gateway + DynamoDB + CloudFront + S3 stay within their free tiers at our scale.
Why this is the conversion pitch: "This dashboard you're looking at runs for £5 a month. Imagine seeing it for *your* account." That's the Tier 1 (Team) value prop in one sentence.