Frontend · Junior · Theory

How is reflow different from repaint, and why does frequent reflow hurt performance?

~4 min by voice

How to approach it

The interviewer checks whether the candidate understands the stages of rendering in the browser (layout → paint → composite), can tell expensive changes from cheap ones, and knows practical ways to avoid triggering unnecessary layout, first and foremost forced synchronous layout.

Have you seen this question in a real interview?

Answers0

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Topics

reflow repaint performance

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Answer by voice

The interviewer will ask this question and listen. Think out loud and ask for a hint if you need one. When you're done, pause or tap “That's my answer”. In about a minute, your score and the points you covered show up here.

Best with headphones · ~4 min