Uptime SLA Calculator
Allowed downtime for any uptime percentage.
Allowed downtime per year
8.77 hr
Allowed downtime windows
Per year8.77 hr
Per month (30.44 day avg)43.83 min
Per week10.08 min
Per day1.4 min
Standard tiers
99.9% = "three nines" is the typical SaaS SLA. 99.99% is the rough ceiling for typical cloud infrastructure. 99.999% is famously hard ("five nines") and usually requires multi-region active-active. Each extra nine costs roughly 10x more to engineer.
About
Enter an SLA percentage (99.9, 99.99, etc.). Get the total allowed downtime per year, month, week, and day. Includes the standard 'nines' tiers and what they look like in real terms.
How to use
- Enter SLA percent.
- Read downtime windows.
FAQ
Why is each extra nine so much harder?+
Going from 99.9% to 99.99% means cutting downtime by 90%, from 8.77 hours/year to 53 minutes. That requires removing single points of failure, multi-region failover, and faster incident response. Each extra nine costs roughly 10x more.