Uptime calculator
What a number in a service level agreement actually permits, per day, week, month and year.
A percentage, like 99.9. A month is 30 days here, and a year 365.
- Per day
- 1 min 26 s
- Per week
- 10 min 5 s
- Per month
- 43 min 12 s
- Per year
- 8 h 45 min
That is the downtime 99.9% permits before the target is missed — planned maintenance included, unless your agreement excludes it.
Common questions
- Is a month 30 days or 31?
- Here a month is 30 days and a year is 365, which is the common convention. Real agreements differ — some use calendar months, so a February outage costs you more allowance than a July one.
- Does an SLA's uptime mean the same as a monitor's?
- Rarely. An agreement usually excludes planned maintenance and anything it calls out of scope, and measures at its own interval. A monitor measures what your customers experienced.
- What does this have to do with monitoring?
- Four nines allows about four minutes a month. You can't defend a number that fine with a check every five minutes — you'd miss most of the budget before the first check fails.
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