API plan limit & overage calculator
Already have plan tiers and real customers? Enter your tiers, paste last month's usage per customer, and see exactly who blew past their limit, what each one owes, how much of your MRR comes from overage, and who would pay less on a bigger plan.
Designing a single price from scratch instead? Use the API usage pricing calculator. To get clean per-endpoint keys for your usage data, try the endpoint normalizer.
1. Your plan tiers
| Plan name | Base fee / mo ($) | Included requests | Overage $ per 1K | Hard cap (blank = none) |
|---|
2. Your customers
One per line: name, plan, monthly requests. Paste straight from a spreadsheet (CSV or tab-separated; a header row is skipped).
3. Results
| Customer | Plan | Requests | Over limit by | Bill / mo | Flag |
|---|
Overage is charged pro rata per 1,000 requests. Requests above a hard cap are rejected (not billed). A "suggested upgrade" appears when a higher tier would give the customer a lower bill without blocking more of their traffic. Runs entirely in your browser; nothing you type is sent anywhere.
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Embed this calculator
Free to embed in your docs, billing help pages or blog. Copy this:
<iframe src="https://api-meter-lab.pages.dev/embed/api-plan-limit-calculator" width="100%" height="900" style="border:1px solid #e3e6ec;border-radius:10px" loading="lazy" title="API plan limit and overage calculator"></iframe> <p><a href="https://api-meter-lab.pages.dev/api-plan-limit-calculator">API plan limit & overage calculator</a> by API Meter</p>
What to do with the result
- Overage share above ~30% of MRR often means included limits are too low, and customers will feel surprised by invoices.
- Suggested-upgrade customers are paying more than a higher plan would cost them. Telling them first builds trust and usually lifts retention.
- Hard-cap hits are rejected requests: lost goodwill and lost revenue. Consider a soft cap with overage instead.
The calculator needs real request counts per customer and plan. API Meter gives you those: route your API through the proxy, tag each response with a customer ID and plan, and read monthly totals from the dashboard.
Get per-customer request counts free Per-customer usage billing guide