Uptime SLA Calculator — Downtime Minutes
Quick answer
Enter a target uptime SLA (for example 99.9%) and see how many minutes of downtime that allows per month and per year. Useful when negotiating SLAs with customers or comparing monitoring alert thresholds.
Calculator
- Downtime per month
- 43.8 min
- Downtime per year
- 526 min (~8.8 h)
How it works
The calculator uses standard calendar assumptions: 30.44 days per month (365.25/12) and 525,600 minutes per year. Downtime budget = (1 − SLA) × total minutes. Pick a preset or type a custom percentage.
For real monitoring with a public status page, see StillOnline uptime monitoring.
FAQ
What does 99.9% uptime mean in minutes?
About 43.8 minutes per month or 8.76 hours per year of allowed downtime.
Is this the same as my hosting SLA?
No—this is a math helper. Your cloud provider, CDN, and app layer each have separate SLAs. StillOnline monitors your health URL from outside.
Should I promise customers 100% uptime?
Avoid it. Use a realistic SLA (often 99.9%+) and a status page for transparency.
Can StillOnline track my SLA automatically?
StillOnline tracks probe results and history (24h on Free, 90 days on Pro). Export and reporting are manual today—use checks + status page for communication.
Need 24/7 monitoring?
Free: 1 URL, checks every 5 minutes, hosted status page.
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