We are used to measure the availability of a web service considering the percent of times in which it is publicly accessible. This is what we call uptime, the terms of time in which a web server is available and accessible on the net. Several hosting providers highlights their own percent of uptime to show the response time and availability of their services on annual, monthly or weekly terms. The opposite measure to uptime is the downtime or disservice time. A website downtime can be caused by server maintenance, network disservices or wrong configurations.
Uptime and downtime are usually used to understand the response time of the services you're going to buy. For example, an annual uptime of 90% will coincide with a total 36 days of downtime during which you will not be able to use your website. A higher uptime between 91,5% and 99,5% will provide you with a higher stability of service.
Check the chart below to take a closer look to several examples of uptime and downtime.
|
Uptime % |
Downtime on annual |
Downtime on monthly* |
Downtime on weekly |
|
90% |
36.5 days |
72 hours |
16.8 hours |
|
95% |
18.25 days |
36 hours |
8.4 hours |
|
97% |
10.96 days |
21.6 hours |
5.04 hours |
|
98% |
7.30 days |
14.4 hours |
3.36 hours |
|
99% |
3.65 days |
7.20 hours |
1.68 hours |
|
99.5% |
1.83 days |
3.60 hours |
50.4 minutes |
|
99.8% |
17.52 hours |
86.23 minutes |
20.16 minutes |
|
99.9% |
8.76 hours |
43.2 minutes |
10.1 minutes |
|
99.95% |
4.38 hours |
21.56 minutes |
5.04 minutes |
|
99.99% |
52.56 minutes |
4.32 minutes |
1.01 minutes |
