Downtime Definition
Intermediate – Web/Development
Reading Time – 1 minute, 08 seconds

The downtime definition is the period when a computing device such as a CPU or a server or a software application such as a website is not functional, not operational, or unavailable to use. Downtime is a measure of system or service reliability and stability. If a system or service downtime is high, that means the system or the service is not reliable and stable.
The network downtime refers to the period the network is not fully operational. The CPU downtime means how long the processor has not been functioning since it was started. The server downtime is the duration that the server is not functional and operational.
The downtime is calculated in minutes or seconds and expressed as a percentage of the time the computing device or the service was down. 99.9% uptime is the industry standard for uptime. Hence, the downtime should be less than 0.01% to incorporate with it.
How to calculate downtime?
Now that you know the downtime definition, how do you calculate it? Consider the functionality of a website for 24 hours. Let’s assume the website was not functioning for 4 hours out of the 24 hours.
The total duration the websites was monitored = 24 hours = (24*60*60) = 86,400 seconds
The total duration the website was not functioning = 4 hours = (4*60*60) = 14,400 seconds
The website downtime = (14,400/ 86,400) * 100% = 16.67%