What the check looks at
X does not use the word shadowban. Since 2023 it has called the practice visibility filtering: a post that breaks its rules can be left out of search and trends, removed from timelines, or ranked down in replies, and X says it labels those posts. From outside X, two of those effects can be measured.
- Search ban. The tool takes the account's ten newest original posts (reposts and replies left out) and runs a public
from:search over the same dates, paging until it has found them all or search runs out. Each post that search never returns is listed with a link, so you can open it and look for a label. - Search suggestion ban. It types the handle into people search and checks whether the account is among the first ten results. X's help says account search prefers complete profiles, and in 2018 a bug kept many accounts out of suggestions, so a miss here is weaker evidence than a miss in post search.
The verdict is worded as a signal: none, weak, strong or unclear. A strong signal means none of the recent posts came back from search; a weak one means a few did not. The shadowban test guide explains each step, what X itself says it limits, and how to appeal, and gives a script that runs the same comparison with more pages.
What to do with the result
Look for a notice from X first: a label under a post, read-only mode, or a locked account are the only certain answers. Then check that the account's email address is confirmed, since X's search help names an unconfirmed email as a reason posts stay out of search. If a strong signal remains after a day or two, appeal through the label or X's help form. To see which search filters apply to a query, use the advanced search builder; to see what search returns for any account, see why X search does not show all results.