Free tool
SLA Uptime Calculator
Enter an SLA percentage to see exactly how much downtime it allows — per day, week, month, and year.
%
Allowed downtime / day
1m 26s
Allowed downtime / week
10m 5s
Allowed downtime / month
43m 50s
Allowed downtime / year
8h 45m
Questions
What SLA percentage is considered "good"?
99.9% ("three nines") allows about 43 minutes of downtime per month and is a common baseline. 99.99% ("four nines") allows only about 4 minutes per month and is typically reserved for critical infrastructure.
Does this account for planned maintenance windows?
No — this is a straightforward percentage-to-time conversion. Most SLAs explicitly exclude scheduled maintenance from the downtime calculation; check your specific SLA's definition.
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