Source: https://uptimeify.io/resources/platform-and-support/glossary/apdex

# Apdex

> Apdex (Application Performance Index) is a standardized score from 0 to 1 that summarizes user satisfaction with response times against a target threshold.

Requests are bucketed as satisfied, tolerating, or frustrated based on a latency target, then combined into a single number. Apdex gives a quick, comparable health score across services.