Uptime Percentage Table — Every SLA Tier from 90% to 99.9999%

Fine-grained uptime percentage reference

Uptime %	Per year	Per month	Per week	Per day
90.0%	36d 12h	73h 0m	16h 48m	2h 24m
95.0%	18d 6h	36h 30m	8h 24m	1h 12m
98.0%	7d 7h 12m	14h 36m	3h 21m	28m 48s
99.0%	3d 15h 36m	7h 18m	1h 40m	14m 24s
99.2%	2d 21h 17m	5h 50m	1h 20m	11m 31s
99.5%	1d 19h 48m	3h 39m	50m 24s	7m 12s
99.7%	1d 2h 17m	2h 11m	30m 14s	4m 19s
99.8%	17h 31m	1h 27m 36s	20m 10s	2m 53s
99.9%	8h 45m 36s	43m 49s	10m 4s	1m 26s
99.92%	7h 0m 29s	35m 4s	8m 4s	1m 9s
99.95%	4h 22m 48s	21m 54s	5m 2s	43.2s
99.97%	2h 37m 41s	13m 8s	3m 1s	25.9s
99.99%	52m 35s	4m 22s	60.5s	8.6s
99.992%	42m 5s	3m 30s	48.4s	6.9s
99.995%	26m 17s	2m 11s	30.2s	4.3s
99.997%	15m 46s	1m 19s	18.1s	2.6s
99.999%	5m 15s	26.3s	6.0s	0.86s
99.9995%	2m 38s	13.1s	3.0s	0.43s
99.9999%	31.5s	2.6s	0.6s	0.086s

Assumptions: Month = 30.44 days. Year = 365.25 days. Values rounded to relevant precision per tier.

How to use this table

Find your target uptime percentage in the left column to see the maximum cumulative downtime allowed at that tier, broken down by measurement period. This is useful for SLA negotiation, incident budget tracking, and setting realistic reliability targets.

For the standard "nines" tiers (99%, 99.9%, 99.99%, etc.) with deeper per-tier explanations and use case guidance, see the Five Nines Availability Table.

Don't see your exact percentage?

For any uptime percentage not listed here, use the Uptime Calculator or Downtime Calculator to compute exact downtime figures instantly.

Small percentage differences matter more than they appear

The difference between 99.9% and 99.95% looks small on paper — half a percentage point — but it represents a 2× reduction in allowed downtime (8h 45m vs 4h 22m per year). At higher tiers, this compounds: the gap between 99.99% and 99.995% is also a 2× reduction, despite the percentages looking nearly identical. Always compare downtime budgets in absolute time, not just percentage points, when evaluating SLA tiers.