Rank

is a measurement system of a Yo-kai's strength within the Yo-kai Watch games, which goes from E to S. The higher the rank, the faster a Yo-kai can become more powerful when they level up. Because of this, some lower-ranked Yo-kai may lose playability as higher ranked Yo-kai become more and more commonplace.

The Yo-kai Watch itself can also be given upgrades in the games in order to find Yo-kai of the same Rank the Watch is and to undo Watch Locks, special energized doors that boast a given Rank that a player's Yo-kai Watch must be at in order to unlock them, of the same Rank as the Watch.

In the anime, Rank is nigh-nonexistent.

Rank E
is the most basic level for all Yo-kai, as well as the standard Rank a newly obtained Yo-kai Watch is set towards. At this rank, the Yo-kai Watch can only find Rank E Yo-kai.

Rank D
is the second-lowest level for all Yo-kai. To upgrade the Yo-kai Watch to this rank in the first game, one has to go to Timers & More, then collect the Watch Cog, Screw, and Spring, get to the Hot Springs at night with Baku's help, evade Gargaros during the game's first Terror Time event while doing so, and defeat Sproink to reclaim Goodsight's Lucky Underwear.

At this rank, the Yo-kai Watch can unlock D-ranked Watch Locks and is able to find Rank D Yo-kai.

Rank C
is the mid-lowest level for all Yo-kai. To upgrade the Yo-kai Watch to this rank in the first game, one has to go to Timers & More, then complete the "Rank C Challenge!" Request.

At this rank, the Yo-kai Watch can unlock C-ranked Watch Locks and is able to find Rank C Yo-kai.

This level also is the lowest level Evolved Yo-kai can be.

Rank B
is the mid-highest level for all Yo-kai. To upgrade the Yo-kai Watch to this rank in the first game, one has to go to Timers & More, then complete the "Rank B Challenge!" Request.

At this rank, the Yo-kai Watch can unlock B-ranked Watch Locks and is able to find Rank B Yo-kai.

Rank A
is the second-highest level for all Yo-kai. To upgrade the Yo-kai Watch to this rank in the first game, one has to go to Timers & More, then complete the "Rank A Challenge!" Request.

At this rank, the Yo-kai Watch can unlock A-ranked Watch Locks and is able to find Rank A Yo-kai.

Rank S
is the highest level for all Yo-kai. To upgrade the Yo-kai Watch to this rank in the first game, one has to go to Timers & More, then complete the "Rank S Challenge!" Request, available after the completion of the main game.

At this rank, the Yo-kai Watch can unlock S-ranked Watch Locks and is able to find Rank S Yo-kai.

Rank SS
is the supreme level for all Yo-kai. This Rank was introduced currently in only Yo-kai Watch: Wibble Wobble.