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Free Tool

Uptime SLA Calculator

Convert an uptime percentage into real allowed downtime. Find out what 99.9% or "five nines" actually means for your service.

%
= 3 nines of availability
Per day
1.4 min
allowed downtime
Per week
10.1 min
allowed downtime
Per month
43.8 min
allowed downtime
Per year
8.77 hr
allowed downtime

SLA reference table

UptimePer monthPer yearTier
90%3.04 days36.52 daysBRONZE
99%7.31 hr3.65 daysSILVER
99.5%3.65 hr1.83 daysSILVER
99.9%43.8 min8.77 hrGOLD
99.95%21.9 min4.38 hrGOLD
99.99%4.4 min52.6 minPLAT
99.999%26s5.3 minPLAT

Month calculated as 30.44 days. Year calculated as 365.25 days. Downtime budgets are cumulative — they don't account for maintenance windows.

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