Uptime SLA Calculator

Convert an uptime percentage into real allowed downtime. Find out what 99.9% or "five nines" actually means for your service.

Uptime Percentage

= 3 nines of availability

Per day

1.4 min

allowed downtime

Per week

10.1 min

allowed downtime

Per month

43.8 min

allowed downtime

Per year

8.77 hr

allowed downtime

SLA reference table

UptimePer monthPer yearTier

90%3.04 days36.52 daysBRONZE

99%7.31 hr3.65 daysSILVER

99.5%3.65 hr1.83 daysSILVER

99.9%43.8 min8.77 hrGOLD

99.95%21.9 min4.38 hrGOLD

99.99%4.4 min52.6 minPLAT

99.999%26s5.3 minPLAT

Month calculated as 30.44 days. Year calculated as 365.25 days. Downtime budgets are cumulative — they don't account for maintenance windows.

Measure your real uptime

An SLA target is a promise — monitoring is the receipt. Scheduled checks on your site, uptime history, and an email within 1–5 minutes when it goes down. Free plan, no card.

Start monitoring →

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