What does "sustained" vs "burst" mean?

Sustained rate is the average throughput your system maintains over a long period. Burst rate is the peak throughput allowed for short spikes. Many APIs enforce both: a high burst allowance for short traffic spikes and a lower sustained limit to protect their infrastructure.

How is the monthly cost estimate calculated?

Monthly requests = sustained requests per second × 60 × 60 × 24 × 30. That number is multiplied by your cost per request to give the monthly estimate. Burst traffic is not included in the sustained monthly calculation.

Can I use fractional rates like 0.5 requests per second?

Yes. All input fields accept decimal values. 0.5 RPS equals 30 requests per minute, 1 800 per hour, and so on.

API Rate Limit Calculator

Convert rate limits between time windows and estimate monthly API costs.

Sustained Rate

Burst Rate

Cost per request (optional)

Window	Sustained	Burst
Per second	0.17	1.67
Per minute	10	100
Per hour	600	6.00K
Per day	14.40K	144.00K
Per month (30d)	432.00K	—
Per year (365d)	5.26M	—

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FAQ

What does "sustained" vs "burst" mean?: Sustained rate is the average throughput your system maintains over a long period. Burst rate is the peak throughput allowed for short spikes. Many APIs enforce both: a high burst allowance for short traffic spikes and a lower sustained limit to protect their infrastructure.
How is the monthly cost estimate calculated?: Monthly requests = sustained requests per second × 60 × 60 × 24 × 30. That number is multiplied by your cost per request to give the monthly estimate. Burst traffic is not included in the sustained monthly calculation.
Can I use fractional rates like 0.5 requests per second?: Yes. All input fields accept decimal values. 0.5 RPS equals 30 requests per minute, 1 800 per hour, and so on.

API Rate Limit Calculator takes a rate limit expressed in requests per second, minute, or hour and converts it to all other windows: per second, minute, hour, day, month, and year. Enter an optional cost per request to get a monthly cost estimate. Separate burst and sustained rate inputs help you model real-world traffic scenarios. Useful for capacity planning, budget estimation, and avoiding overage charges.