SLA Calculator
Calculate your allowed downtime based on SLA percentage.
Select SLA Level
8h 46m
allowed downtime
43m 50s
allowed downtime
10m 5s
allowed downtime
1m 26s
allowed downtime
SLA Reference Table
| SLA % | Nines | Yearly Downtime | Monthly Downtime |
|---|---|---|---|
| 99% | 0 nines | 3d 15h 40m | 7h 18m |
| 99.5% | 0 nines | 1d 19h 50m | 3h 39m |
| 99.9% | 1 nines | 8h 46m | 43m 50s |
| 99.95% | 1 nines | 4h 23m | 21m 55s |
| 99.99% | 2 nines | 52m 36s | 4m 23s |
| 99.999% | 3 nines | 5m 16s | 26s |
Understanding SLA
Service Level Agreements (SLAs) define the expected uptime of a service. This calculator helps you understand what each SLA percentage means in terms of actual allowed downtime.
What is SLA?
An SLA (Service Level Agreement) is a commitment between a service provider and customer that defines the expected availability of a service. For example, 99.9% uptime means the service should be available 99.9% of the time.
The "Nines" Concept
In the industry, uptime is often expressed as "nines". Three nines (99.9%) allows about 8.76 hours of downtime per year. Four nines (99.99%) allows only 52.6 minutes. Five nines (99.999%) is considered "high availability" with just 5.26 minutes of allowed downtime per year.
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