Firestore Cost Simulator
Plug in your tenant profile and watch the monthly bill move. The simulator compares a naive architecture (read every raw doc on every dashboard load) against a daily-rollup architecture (one pre-aggregated doc per day).
Firestore cost simulator
$0.06 / 100K reads · North AmericaPlug in your own numbers. Assumes a 90-day dashboard period and a 30-day month.
Reads / dashboard load: 1,877Monthly reads: 1,689,300,000
Reads only. This figure excludes writes ($0.18 / 100K) and — for the rollup architecture — Cloud Function invocations ($0.40 / million past the 2M free tier) plus compute time. For a tenant logging 200 income entries/day, that's roughly 6K extra invocations per month per tenant: a few dollars at scale, but worth knowing before you ship.
Pricing assumes North America Firestore reads at $0.06 per 100K, a 90-day dashboard window, and a 30-day month. The math is in the source — open the component to audit it.
Context for these numbers: Firestore Architecture for Scaling Read-Intensive Multi-Tenant Software.