Claws. Melee Attack Roll: +6, reach 5 ft. Hit: 8 (1d8 + 4) Slashing damage. If the target is a Large or smaller creature and the allosaurus moved 30+ feet straight toward it immediately before the hit, the target has the 344 Prone condition, and the allosaurus can make one Bite attack against it.
RollQuest ships the D&D 2024 SRD as a content pack, on a 5e character sheet that does the maths - roll from the sheet and let the numbers work themselves out. Free to start.