What's the difference between 1:64, 1:24, and 1:18 scale diecast cars?

1:64 is the standard small Hot Wheels/Matchbox size that fits track sets and multipacks. 1:24 and 1:18 are larger display-oriented collectibles with more detail, opening doors, and heftier metal bodies, which is why brands like Jada and Maisto price them higher.