Site Reliability Engineering
Availability SLA Calculator
Enter an availability target to compute allowed downtime in minutes and hours per month, quarter, and year, with five-nines reference comparison.
No data is transmitted — everything runs locallyTool
Example — Four nines — 99.99% availability
Annual downtime
52.6 min
≈52 min/year
Monthly downtime
4.3 min
Weekly downtime
1.0 min
About this tool
Availability SLA Calculator
The Availability SLA Calculator converts availability percentage to allowed downtime minutes per month, quarter, and year, with DORA tier and five-nines reference comparison.
• Convert a 99.95% SLA to minutes of allowed monthly downtime for a contract review
• Understand the practical difference between 99.9% and 99.99% uptime commitments
• Calculate quarterly downtime allowance for a customer SLA conversation
• Model the maintenance window budget available under a given SLA target
Affiliate disclosure
Sponsored tool. This tool is brought to you by our partners. No data is collected or transmitted.View the availability this SLA describes — UptimeRobot checks every 60 seconds
FAQ
What does this tool tell you?
The Availability SLA Calculator converts availability percentage to allowed downtime minutes per month, quarter, and year, with DORA tier and five-nines reference comparison.
What affects the result most?
99.9% uptime = 43.8 min/month downtime, 8.76 hr/year. 99.99% uptime = 4.38 min/month downtime, 52.6 min/year. 99.999% (five nines) = 26.3 sec/month — extremely difficult to achieve end-to-end.
How should I use the result?
The calculation is deterministic — the same inputs always produce the same output — so the most useful workflow is to vary one input at a time and see which factor moves the result most. That tells you where to focus your attention before committing to a decision.
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