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.
Furthermore, Gimmi can also warp / rewrite "everything" (== Nigh-Omnipotence) and so far also has both OmniLock and (at least Type 2) Transduality, both of which are enough to easily scale Gimmi to Outerversal at least. They also transcend their very own author (just another character within their verse) quite literally, so "Outerversal" might well be a lowball for them, too.