What to check on a skeleton screen
A skeleton screen draws the shape of the content that is about to arrive. When the position, count or line count of its blocks does not match the real content, the page jumps the moment the data lands and the smoothing effect is lost. Tick the checklist and the tool tallies what you have confirmed and lists what is left; add block counts and it compares them with the real content.
How the tally works
The share is ticked items divided by total items, and every unticked item stays in the list below. The block comparison is skeleton blocks minus real blocks, and the shift warning appears only when that difference is not zero. The items collect points that the W3C accessibility guidelines on conveying state and the common web performance metrics for layout shift both cover.
Limits
As of October 2026 there is no official standard for how long a skeleton should stay up or how many blocks it needs, so this tool proposes no value and gives no score. It also does not decide between a spinner and a skeleton. Stop the shimmer under prefers-reduced-motion for people sensitive to movement.
Frequently Asked Questions
There is no official recommended display time, so this tool proposes none. Measure your real response times and prepare a separate screen for the cases that run long.
When the resulting layout cannot be known in advance there is no block shape to imitate, so the advantage of a skeleton shrinks. This tool does not decide between the two for you.
If the real content has more or fewer blocks than the placeholder, the layout shifts by that difference when it arrives. Matching block and line counts reduces the shift.