Answer:

Ghouls are rated based upon various factors, including their basic strengths, activity levels, influence and hostility towards investigators. In modern-day, there are six rating levels, from SSS (the most powerful) to C (the weakest).

If you mean Tokyo Ghoul as in the Anîme then here it is.

Answer:

-SSS rated

• Criteria is unclear.

-SS rated

• Multiple Special Class Investigators are needed.

-S+ rated

• Equivalent to the ability of an average Special Class Investigator. (approx.)

-S- rated

• Equivalent to the ability of an average Associate Special Class Investigator. (approx.)

-A rated

• Comparable to a First Class Investigator. These ghouls are usually set as a target and some ghouls might develop a second tail/tentacle.

-B rated

• Comparable to a Rank 1 to Rank 3 Investigator. These ghouls should have their Kagune mastered and are usually a small threat to the World.

-C rated

• Ghouls of smaller ability, these ghouls usually can't fight any ghoul investigators and only attack unarmed people.