Uptime and downtime with 99.9999999 % SLA

2025-11-27:

It's always DNS. I built uptime mongers to monitor the DNS security issues that standard services ignore: parent zone delegation changes, stale DNSSEC signatures, expired RRSIGs. Get alerted when nameservers change at your registrar without your permission.

SLA & Uptime Calculator

How much downtime corresponds to your SLA?

%

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

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

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

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.