User blog comment:Pualover/Overlord Power Level/@comment-101.127.209.29-20180305181213/@comment-5480911-20180306054830

1-7: Tier 1

8-14: Tier 2

15-21: Tier 3

22-28: Tier 4

29-35: Tier 5

36-42: Tier 6

43-49: Tier 7

50-56: Tier 8

57-63: Tier 9

64-70: Tier 10

71+ Super tier magic

Yes you can apply race level as they exist, Several characthers in this novel were confirmed to have race leves in the new world: Go Gin, Frost Dragon Lord, Pei Riyou. Buser etc.

You see he can't use tier 7 as he is not at that level, MAruyama posted a long while back that 7 maigc classes are equal to one tier level, I have been part of this community for over 3 years and is one of it's top contributers so don't say my info is wrong, You want the source go to reddit and type February 2018 overlord anthology it has all the information published from maruyama including the original web novel, All translated tweets, Extra side stories and everything else.