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The Guide to Microsoft Teams Phone System
25 Jan, 2026
Free Tool
Network Uptime Calculator
Calculate allowed downtime at every SLA level, estimate the financial impact of outages, and understand what each “nine” of availability really means for your business.
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Approximate revenue your business generates per hour
Used to calculate productivity loss during downtime
Complete SLA Reference
| SLA Level | Downtime / Month | Downtime / Year | Tier Name | Typical Use |
|---|---|---|---|---|
| 99% | 7h 18m | 3d 15h 36m | Two Nines | Budget hosting, dev/test |
| 99.5% | 3h 39m | 1d 19h 48m | — | Standard broadband |
| 99.9% | 43m 50s | 8h 45m 36s | Three Nines | Business-grade services |
| 99.95% | 21m 55s | 4h 22m 48s | — | Enterprise cloud |
| 99.99% | 4m 23s | 52m 34s | Four Nines | High-availability |
| 99.999% | 26s | 5m 15s | Five Nines | Carrier-grade |
Downtime is calculated as (1 - SLA%) × total hours in the period. Monthly = 730 hours, yearly = 8,760 hours. Actual SLA terms vary by provider. Talk to our network team
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