Browser & Web Performance · Senior · Question 10 of 75

What is the frame budget for 60 Hz rendering and why is it lower than 16.7 ms in practice?

1About 100 ms, as in the RAIL model's response goal
✓Correct answer: About 16.7 ms per frame, but the browser needs part of it for style, layout, paint and compositing, so JS gets roughly 10 ms
3Exactly 16.7 ms just for JavaScript

Explanation

On 120 Hz screens the budget is about 8 ms. Work beyond the budget means dropped frames and janky scrolling or animation.

Further reading

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