API SLA Downtime Calculator
Convert an uptime target into allowed downtime and track remaining monthly error budget.
Editable usage, rate, and operating assumptions
Scenario totals and unit economics
Set API availability targets
API SLA Downtime Calculator
Translate an uptime commitment into allowed downtime and remaining error budget.
Frequently asked questions
Practical answers for applying this calculator to a production API billing or usage plan.
How much downtime does 99.9% allow?
In a 30-day month, 99.9% availability allows about 43.2 minutes of downtime. The exact amount changes with the measurement period.
What counts as downtime?
Define this in the SLA. Many agreements exclude planned maintenance or measure only failed eligible requests, specific regions, or covered endpoints.
What is an error budget?
It is the amount of unreliability permitted by the target. Teams can use the remaining budget to balance release speed against reliability risk.
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