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Uptime SLA Calculator — 99.9% Means How Much Downtime?

Uptime SLA Calculator — 99.9% Availability Means How Much Downtime? ⏱️ Uptime SLA Calculator Translate SLA percentages into real downtime. Know exactly what “99.9%” means before you sign a contract. SLA → Max Downtime 99.90% Or enter exact SLA % Three Nines (99.9%) Downtime Budget Planner SLA percentage How often do incidents occur? Once per […]

Jack Pauley March 13, 2026 6 min read






Uptime SLA Calculator — 99.9% Availability Means How Much Downtime?


⏱️ Uptime SLA Calculator

Translate SLA percentages into real downtime. Know exactly what “99.9%” means before you sign a contract.

SLA → Max Downtime

99.90%


Three Nines (99.9%)

Downtime Budget Planner






Actual Availability Calculator




SLA Comparison Table — Industry Standards

Availability Nines Downtime/year Downtime/month Downtime/week Grade



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