The Superhero Database Classification number, or SHDB Class, is a number that represents the overall 'power' of a character. All traits of a character are used for calculating the Classification.
What it DOESN'T mean
This doesn't mean that a higher class would always beat a lower class character. But the bigger the difference in Class is, the more obvious it is who'll win in a fight.
How is this calculated
( INT^1.3 + (STR*0.5 )^2 + (SPE*0.5)^2 + DUR^1.6 + (POW + (SPS*SPL))^2 + COM^1.8 ) ^ TIER
Super Power Score and Level
Every Super Power has a score (SPS) that is used to calculate the Class. Each Super Power also has 3 levels (SPL). The level is set when connecting that Super Power to a character. The level determines the final score, of the Super Power, being used in the calculation.
At the top of this hierarchy sits of sea of fragments and city of books, which would qualify for Low 1-A (at the very best). Featherine does indeed transcend these two realms, qualifying for either one or two layers into outerversal (depending on how you place the city in relation to the sea). Similarly, so too does the creator realm sit at "only" 3 layers into outer since, again, it is not at all ineffable not fully transcendent as it would require to be H1-A.
With this said, The Presence stomps and it's not close.