Browser & Web Performance · Middle · Question 28 of 75

How is the CLS value for a page visit computed?

1Only the first layout shift counts
2All shifts during the visit are added together
✓Correct answer: Shifts are grouped into session windows (max 5 s, gaps < 1 s), and the window with the largest total is reported

Explanation

Session windows keep CLS fair for long-lived pages like SPAs that would otherwise accumulate an ever-growing score.

Further reading

web.dev: Cumulative Layout Shift ↗

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