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Availability Table (90%-99.999% Uptime)

Jenda Tovarys
Updated on May 4, 2022

Availability (uptime) is calculated as a time a given service was unavailable over a specified period of time. For example to reach 99.9% availability over a period of a month, the maximum allowed downtime is 43.2 minutes.

The availability table below shows how much downtime is permitted to achieve a desired availability level.

Availability level Allowed unavailability window
(uptime) per year per quarter per month per week per day per hour
90% 36.5 days 9 days 3 days 16.8 hours 2.4 hours 6 minutes
95% 18.25 days 4.5 days 1.5 days 8.4 hours 1.2 hours 3 minutes
99% 3.65 days 21.6 hours 7.2 hours 1.68 hours 14.4 minutes 36 seconds
99.5% 1.83 days 10.8 hours 3.6 hours 50.4 minutes 7.20 minutes 18 seconds
99.9% 8.76 hours 2.16 hours 43.2 minutes 10.1 minutes 1.44 minutes 3.6 seconds
99.95% 4.38 hours 1.08 hours 21.6 minutes 5.04 minutes 43.2 seconds 1.8 seconds
99.99% 52.6 minutes 12.96 minutes 4.32 minutes 60.5 seconds 8.64 seconds 0.36 seconds
99.999% 5.26 minutes 1.30 minutes 25.9 seconds 6.05 seconds 0.87 seconds 0.04 seconds
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Jenda Tovarys
Jenda leads Growth at Better Stack. For the past 5 years, Jenda has been writing about exciting learnings from working with hundreds of developers across the world. When he's not spreading the word about the amazing software built at Better Stack, he enjoys traveling, hiking, reading, and playing tennis.
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