Apdex is a numerical measure of user satisfaction with the performance of enterprise applications. It converts many measurements into one number on a uniform scale of 0-to-1 (0 = no users satisfied, 1 = all users satisfied).


Application Performance Index

The method of calculation was developed by an alliance of companies all working in the field of application performance. Newtest (Auditec) was formed part of the working group during the later years of the 2000.

The index is based on three zones of application responsiveness:

  • Satisfied: The user is fully productive. This represents the time value (T seconds) below which users are not impeded by application response time.
  • Tolerating: The user notices performance lagging within responses greater than T, but continues the process.
  • Frustrated: Performance with a response time greater than F seconds is unacceptable, and users may abandon the process.

The Apdex formula is the number of satisfied samples plus half of the tolerating samples plus none of the frustrated samples, divided by all the samples. ip-label uses this index in relation to their end-user quality of experience solutions used to monitor application performance (APM).

Source / More informationApdex Alliance