Frontend Developer
hardbrowser-rendering-critical-path

Explain the browser rendering process (critical rendering path).

Answer

The critical rendering path is how the browser turns HTML/CSS/JS into pixels: 1) Parse HTML → DOM 2) Parse CSS → CSSOM 3) Combine DOM + CSSOM → Render Tree 4) Layout (calculate sizes/positions) 5) Paint and Composite **Performance tips:** minimize render-blocking CSS/JS, reduce layout thrashing, and avoid heavy work on the main thread.

Related Topics

PerformanceBrowsersJavaScript