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Free SLA Uptime Calculator

Calculate allowable downtime from uptime percentage.

Service Level Agreement

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Allowable Downtime

Daily
1m 26s
Weekly
10m 4s
Monthly
43m 49s
Yearly
8h 45m 56s

Understanding SLA Availability

SLA (Service Level Agreement) availability defines the guaranteed percentage of time a service will be operational. Meeting high availability standards (like "Five Nines" or 99.999%) requires redundant systems and rigorous network monitoring.

Common SLA Tiers

  • 99.9% ("Three Nines"): Standard for commercial ISP services. Allows ~43 minutes of downtime per month.
  • 99.99% ("Four Nines"): Enterprise standard. Allows ~4 minutes of downtime per month.
  • 99.999% ("Five Nines"): Carrier/Telco grade. Allows only ~26 seconds of downtime per month.