Classification: Human, Demon contractor
Threat level: Dragon-
Physical strength: At least millions of tons range(town+, even mid-series Oga was capable of finger flicking someone kilometers away)
Destructive capacity: At least island+ (Baby Beel could destroy an island simply by drop kicking it and he's the source of Oga's power, Oga and Fuji were also hyped as being capable of making hell on earth without anyone being able to stop them which would imply they're above most or all mankind has to offer)
Durability: At least city+ (It was implied nothing done previously by Oga would even faze Fuji and Oga used a near city sized magic circle to beat Takamiya. Even much earlier in the series he had feats that were easily multi city block+ with only fist sized circles, so saying that a city sized circle had city level power would easily be reliable as a low-end. End of series Oga is clearly superior to Fuji.)
Speed: Hypersonic+ (Had feats which were easily supersonic+ since mid-series, his stats augment dramatically in the final arc)
Intelligence: Low. Oga is pretty stupid and straight to the point. Although he is somewhat of a skilled and creative fighter.
Stamina: High. Can likely fight for hours non-stop.
Standard equipment. None usually except a milk bottle for Baby Beel, and Beelzebub himself if you take him as standard equipment.