Response Time
Response time is how long a service takes to respond to a request, usually measured in milliseconds.
Response time is a core performance and reliability signal. A service can be "up" yet so slow it is effectively unusable, which is why monitoring often alerts on a response-time threshold as well as on hard failures.
It is closely related to TTFB (time to the first byte) and is frequently used as an SLI, for example, "95% of checks respond in under 800 ms".
How fast does your service really respond?
Measure your site's response time in milliseconds. A service can be up and still too slow to be usable. Check it free.
Related terms
TTFB (Time To First Byte)Time To First Byte (TTFB) is the time between making a request and receiving the first byte of the response.SLI (Service Level Indicator)A Service Level Indicator (SLI) is the actual measured value of a reliability metric: the number you compare against your SLO and SLA.Real User Monitoring (RUM)Real User Monitoring (RUM) measures performance and errors from the browsers of your actual visitors, capturing what real people experience.
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