✦ Free tool
Uptime calculator
Convert an uptime or SLA percentage into allowed downtime - or work out the uptime from your actual downtime.
Overview - Uptime calculator
Per day-
Per week-
Per month-
Per year-
SLA downtime table
| Uptime | Per day | Per week | Per month | Per year |
|---|---|---|---|---|
| 99% | 14m 24s | 1h 40m 48s | 7h 18m 17s | 3d 15h 39m |
| 99.5% | 7m 12s | 50m 24s | 3h 39m 8s | 1d 19h 49m |
| 99.9% | 1m 26s | 10m 4s | 43m 49s | 8h 45m 56s |
| 99.95% | 43.2s | 5m 2s | 21m 54s | 4h 22m 58s |
| 99.99% | 8.6s | 1m | 4m 22s | 52m 35s |
| 99.999% | 0.9s | 6s | 26.3s | 5m 15s |
Month = 30.44 days, year = 365.24 days. Learn more in How uptime is calculated.
How much downtime does 99.9% uptime allow?
About 43 minutes 50 seconds per month, or roughly 8 hours 46 minutes per year.
How much downtime does 99.99% uptime allow?
About 4 minutes 23 seconds per month, or roughly 52 minutes 36 seconds per year.
How is uptime percentage calculated?
Duration-based uptime = (total time − downtime) ÷ total time × 100. Check-based uptime = successful checks ÷ total checks × 100.
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