Oil filter adapter nut size
 

I tried all the way up to 22 mm and then 24 mm then I read 30 mm. Please help. It's the nut behind oil filter. Thanks.

You are trying to remove the oil filter stud itself?

I have to ask why? Is it damaged or broken? Or you are trying to change it to a different size (which is the common reason for removing them)?

Because the fact Toyota uses a 3/4 x 16 stud is a total gift for American owners, it gives us access to a vast array of high quality filters for very cheap vs. most asian metric filter stud sizing.