I read your tier list, or your Steam hours, and show my working.
01
Each game you ranked counts for the row it's in: an S game pulls hard, an F game pushes away. Without a tier list, every game you've played for two hours or more counts the same. What kind of game each one is comes from its Steam tags.
02
About 9,000 well-reviewed Steam games are scored by how far their tags point where yours do, and well-known, well-loved games come first among the ones that fit. Your own games that point at a hunch hardest are pinned above it.
03
It hides your ranked games two at a time and guesses which one you put higher. Your number out of a hundred says how readable your board is. Your stars on each hunch say how good the guess was.
From your tier list when this browser has one for your library, otherwise from your Steam hours. It adds up the Steam tags of your games, each weighed by the row you put it in, and scores every well-reviewed game you don't own by how well its tags fit, with well-known, well-loved games first among those that fit. No two hunches lean on the same one of your games more than twice, and only one comes from any series.
On the tier lists made here, with 30% of each board hidden and 9,000 games ranked from the rest, a hidden S or A game reached the top five twice as often as when going by hours alone, and more than twice as often as when going by Steam's reviews alone. The tally on your reading shows how well it reads your own board, and your stars on each hunch are how it learns where it misses.
Hours say what you played, not what you liked: a game you ground through and a game you loved can have the same hours. A tier list says which you liked. The reading tells you the one change to your board that would help most: rank games you've played that aren't on it yet, split a crowded row, or put your top row in order.
Yes. A row you put in order by hand is read in that order: the first game counts a little more than the last, and the order is part of the test the reading runs on you. A row filled straight from the deck isn't, because the deck deals your most-played games first.
The reading needs your library to know what you own and have played. In Steam, open Edit Profile, then Privacy Settings, and set both "My profile" and "Game details" to Public.
For each hunch shown: the library's Steam ID, the game, its place among the five and when, and your stars if you give them, so a later look can tell whether a hunch got played. Your tier list stays in your browser; it is sent to be read, not kept. No account is made.