Technology & Computing
Server SLA Uptime Downtime Calculator
Convert an SLA uptime percentage (e.g. 99.9%) into allowed downtime per day, month and year.
Your inputs
Change any value to update the result instantly.
Allowed downtime per year
525.6 minutes
Downtime per day
1.44 min
Downtime per month
43.2 min
Downtime per year
525.6 min
Uptime target
99.9%
Five nines (99.999%) allows just over 5 minutes of downtime a year.
Formula and working
Downtime = (1 − uptime%) × period length
- 1
Collect the inputs
SLA uptime target = 99.9
- 2
Apply the formula
Downtime = (1 − uptime%) × period length
- 3
Result
Allowed downtime per year = 525.6 minutes
Frequently asked questions
Important limitation
This is an educational estimate based only on the values and formula shown. Verify current rates, rules, units, and professional standards before relying on the result. It is not personalized financial or investment advice.
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