I tend to overthink things. I know pillowcases are simple, but I got stuck.

the lenght is 27 inches for the main piece. What is the width? 27 x ?

The main piece is 27" X width of fabric.

Check on-line under "pillowcase" and you will find instructions!

Yes, width of fabric.

Any one know the length if I want to make it king size??

i'd make the big piece she's asking about the acyual length of the pillow, the contrast piece would be the same as for the regular size

Thanks for help. I got it now. I wasn't taking in account for the entire size of the pillow.

For the King size- I just put the fabric against one of my store bought cases. :D

I've been told and my directions say 3/4 yd for a standard pillowcase and 1 yard for a king. That is not adding the cuff and whatever trim.

Here are the numbers
Your width of fabric from salvage to salvage is generally 42-44. Cut off the salvage.
Just remember these numbers:
Standard = 42, 27, 9, 2.
Width = 42
Length = 27
Accent (end piece) = 9 (x42)
Trim = 2 (x42) This is optional
King = 44, 36, 9, 2
The 9" and 2" strips will be the width of the fabric (42 or 44).