A practical guide to measuring React rendering performance, identifying slow components, understanding render causes, and fixing performance problems without premature optimization.
Introduction
A React application can feel slow for many different reasons.
Maybe clicking a button causes a noticeable delay. Maybe typing into a search field feels laggy. Maybe opening a dashboard takes too long. Or perhaps a component takes hundreds of milliseconds to render even though the UI doesn't look particularly complicated.
The difficult part isn't knowing that something is slow.
