Uptime percentages and monthly downtime budgets
Translate an uptime target into allowed downtime over exactly 30 days. A 99.9% target permits 43.2 minutes in this fixed period.
Uptime percentages and monthly downtime budgets
| Uptime (%) | Downtime (min) | Downtime (s) |
|---|---|---|
| 90 | 4320 | 259200 |
| 95 | 2160 | 129600 |
| 98 | 864 | 51840 |
| 99 | 432 | 25920 |
| 99.5 | 216 | 12960 |
| 99.9 | 43.2 | 2592 |
| 99.95 | 21.6 | 1296 |
| 99.99 | 4.32 | 259.2 |
| 99.999 | 0.432 | 25.92 |
| 100 | 0 | 0 |
Formula & method
downtime min = 30 × 24 × 60 × (1 − uptime% / 100)What can change the answer
This is arithmetic, not a service guarantee. Providers differ in excluded maintenance, measurement windows and compensation rules. Calendar months do not all have 30 days.
Sources & definitions
Method checked:
Continue with a related task
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