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Uptime and downtime with 99.9999999 % SLA

2025-11-27: It's always DNS, isn't it? I built an uptime monitoring service uptime mongers to monitor the DNS security issues that standard services ignore: parent zone delegation changes, stale DNSSEC signatures, expired RRSIGs. Other check types: PING, HTTP, TOR, TCP, PUSH.

SLA & Uptime Calculator

How much downtime corresponds to your SLA?

%
(enter SLA level and hit the <enter> key)

SLA level of 99.9999999 % uptime results in the following periods of allowed downtime:

Daily 8.6e-05s
Weekly 0.0006s
Monthly 0.0026s
Quarterly 0.0079s
Yearly 0.032s

Direct link to the page with these results: uptime.is/99.9999999 (or uptime.is/nine-nines)

The SLA calculations assume a requirement of continuous uptime (i.e. 24/7 all year long) with additional approximations as described in the source. uptime.is was originally implemented in newLISP, which had powered uptime and downtime calculations for more than a decade.

For convenience, there are special CEO and SEO friendly links for N nines: three nines, four nines, five nines, six nines etc.