PayAPIKey

API Budget & Quota Calculator

Turn a monthly API budget into token, request, and per-user usage quotas with an operating reserve.

API budget calculatortoken quota calculatorAPI spend limit calculator

API Budget & Quota Calculator

Convert a fixed monthly budget into safe token, request, and per-user limits.

Usable budget
$640
After fixed cost and reserve
Token quota
320M
Total monthly capacity
Request quota
160K
At average request size
Per-user quota
3.2M
1,600 requests
Variable budget before reserve$800
Reserved amount$160
Cost per average request$0.00
Set the hard monthly token cap near 320M and alert before that limit so delayed usage events cannot exhaust the full budget.

Frequently asked questions

Practical answers for applying this calculator to a production API billing or usage plan.

Why reserve part of an API budget?

A reserve covers retries, traffic spikes, larger prompts, price changes, and usage that arrives before metering or alerts catch up.

Should quotas use registered or active users?

Use expected active users for realistic allocation, then enforce hard account or workspace caps so unexpected activation cannot exceed the total budget.

How often should an API budget be reviewed?

Review after model, pricing, product, or traffic changes and compare forecast with actual spend at least once per billing cycle.