Ha Avalability Table

Availability Table - Cheat sheet

Availability level	Downtime per year	Downtime per quarter	Downtime per month	Downtime per week	Downtime per day	Downtime per hour
90% (“one nine”)	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% (“two-nines”)	3.65 days	21.6 hours	7.2 hours	1.68 hours	14.4 minutes	36 seconds
99.50%	1.83 days	10.8 hours	3.6 hours	50.4 minutes	7.20 minutes	18 seconds
99.9%(“three nines”)	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%(“four nines”)	52.6 minutes	12.96 minutes	4.32 minutes	60.5 seconds	8.64 seconds	0.36 seconds
99.999%(“five nines”)	5.26 minutes	1.30 minutes	25.9 seconds	6.05 seconds	0.87 seconds	0.04 seconds