Uptime Monitoring and What 99.9% Means
Uptime is the percentage of time your site is available to visitors. You will often see figures like 99.9% quoted in hosting and SLA documents, but the practical meaning of those decimal points is easy to underestimate.
This article translates uptime percentages into real-world downtime so you can judge what level you need.
What Counts as Downtime
Not every blip is treated as downtime. Brief, planned maintenance windows are usually excluded from the figure, while unexpected outages that stop visitors using your site are not.
Reading the small print matters: two providers quoting the same percentage may measure it quite differently. We are happy to explain exactly how your figure is calculated.
- Unplanned outages count against uptime.
- Agreed maintenance windows are usually excluded.
- Slow responses may or may not count, depending on terms.
Turning Percentages Into Time
A small difference in percentage equals a large difference in allowed downtime. The table below shows roughly how much downtime each figure permits per year.
How We Monitor It
Automated checks contact your site every few minutes from multiple locations. If it fails to respond, we are alerted immediately — often before you or your customers notice anything is wrong.
| Uptime | Downtime per Year | Downtime per Month |
|---|---|---|
| 99% | About 3.65 days | About 7.2 hours |
| 99.9% | About 8.8 hours | About 43 minutes |
| 99.99% | About 53 minutes | About 4.3 minutes |
Frequently Asked Questions
Is 100% uptime possible?
In practice, no. Even the largest providers plan for some downtime. Higher figures cost more and have diminishing returns for most sites.
If you need a hand with any of this, your Progressive Robot delivery team is ready to help. Raise a ticket from the Support area of your client portal or speak to your account manager and we will guide you through the next steps.