How the ranking works
X's search has a Top order, which is its own ranking by engagement. The finder asks for an account's posts in that order, keeps the ones the account wrote, and sorts them by like count. That takes one search, so the answer comes back in about a second. The like counts are the ones on X at the moment you run it.
For the method behind an exact list, and the most liked posts on all of X, read our guide to the most liked tweets. To study how an account posts rather than its best posts, the profile analyzer reads its recent posts and the engagement calculator turns counts into a rate.