SLA Calculator
Calculate allowed downtime for any SLA percentage, reverse-calculate an SLA from real downtime, and combine multiple dependent service SLAs into a composite uptime target.
Assumptions: one month = 30 days; quarter = 3 selected months; year = 365 days; day = 24 hours.
Other SLA presets
Other periods
Choose the measurement period and unit, then enter the observed downtime.
Equivalent rate in other periods
Series model: every service must be available. Assuming independent failures, composite availability = 100 × (SLA₁ / 100) × (SLA₂ / 100) × … . This is not a parallel/redundant architecture model and does not account for correlated failures.
Other periods
A provider SLA is a financial commitment, not a prediction of actual availability. This estimate does not calculate credits or contractual exclusions.