Profiling with React DevTools

The profiler records what rendered, how long it took, and why it happened. Reading a flame graph correctly is most of the diagnostic work.

What this lesson covers

• Record a realistic interaction, not an idle page
• Read the flame graph and the ranked chart
• Turn on "why did this render" to get the cause

This lesson sits in Measuring Performance, part of React Performance Engineering. It assumes what came before it and leads directly into the next lesson in the module.