1)Ordinary Human class: In this class we have normal humans and normal Rukongai souls. They have minimal amount of reiryoku than any other race.
2)SuperHuman class: This class contains souls who are going through shinigami tutelage and ordinary nobles with no shinigami training. There is also newly born hollow belong into this class. They possess below average amount of reiryoku.
3)Non-seated Shinigami: This are shinigami who graduated from the academy with no exceptional skills and are average except in one of the four shinigami arts and they have no seats in their division. They possess a zanpakuto which has no shikai or bankai. They possess average amount of reiryoku.
4)Average Seated Shinigami: This consists of shinigami occupies the double digited seats in a division. They have have recently unlocked a shikai and possess average skill in all of the four shinigami arts. Newly born Gillians also belong in this class.Those in this class possess above average amount of reiryoku
5)Senior Seated Shinigami: This are shinigami who occupy a single digited seat in their division(9th to 3rd).They are highly trained with their shikai and they have elevated one or two of their skills beyond average in the shinigami arts.They possess the same amount of reiatsu as the previous class but differentiated by how they use it.
6)Average Lieutenant Shinigami: This consists of newly promoted lieutenants with lack of enough experience. They have mastered their shikai and all of their skills are above average in the shinigami arts.They possess large amount of reiryoku.Newly born adjuchas belong into this class.
7)Advanced Lieutenant-class Shinigami:This are lieutenants with more than two decades of experience.They have mastered their shikai or have recently unlocked their Bankai. All their skills in the four shinigami arts are beyond average. They possess vast amount of reiryoku.
8)Average Captain-class Shinigami: This are shinigami who are newly promoted to the rank of Captain. They are familiar with their Bankai with no problem and they have also perfectly mastered one of the four shinigami arts. They also possess immense amount of reiryoku. A newly born Vasto lorde belong in this class.(ex:SS arc Sajin Komamura, Nnoitra Gilga and Candice Catnipp)
9)Advance Captain-class Shinigami:This are Captains with more than a decade of experience as a Captain. They are more powerful than your average Captain as they have mastered 2 to 3 of the four shinigami arts. They possess massive amount of reiryoku and 1st réssurecion of the top espada belong in this class.
10)Senior Captain-class Shinigami: This captains are the pinnacle of a shinigami as they have mastered their Bankai and of the four shinigami arts. They class is so powerful than a captain's shikai of this class is enough to handle an average Captain's Bankai. They have overwhelming amount of reiryoku which is double that of a normal Captain.
11)Royal Guard-class Shinigami: This is the pinnacle of the shinigami race for their anomalies. This is a level of power only demonstrated by an individual of Squad Zero or Yamamoto. Their reiryoku has transcended the normal boundary of shinigami and advanced into almost transcendence. They are able to affect a whole realm with their reiryoku.(ex:CFYOW Zaraki, Gerarld Valkyrie, Jugram Haschwalt, TYBW Uryu Ishida and Lille Barro)
12)Soul King-class: This individuals are able to maintain or destroy the 3 realms of bleach and are far beyond the normal supernatural races.(Soul King Juhabach, TYBW Aizen and Full power Ichigo)