Standard MOI Table

Body	Axis	MOI
Thin rod (M, L)	Centre, perp.	$ML^2$ /12
Thin rod	End, perp.	$ML^2$ /3
Ring (M, R)	Central axis	$MR^2$
Ring	Diameter	$MR^2$ /2
Disc (M, R)	Central axis	$MR^2$ /2
Disc	Diameter	$MR^2$ /4
Solid sphere (M, R)	Diameter	$\frac{2}{5}$$MR^2$
Hollow sphere (M, R)	Diameter	$\frac{2}{3}$$MR^2$
Solid cylinder (M, R)	Central axis	$MR^2$ /2

Memory trick: Ring > Hollow sphere > Disc = Solid cylinder > Solid sphere (for same M, R about natural axis). The more mass is concentrated far from the axis, the larger the MOI.