Well this is interesting!! I called several bakeries in the Columbus metro area and here is the answers I got for what they consider a FULL sheet cake (and their prices) :

27 x17 (Annies - 42.50))
18x26 (Buehelers - 42.00)
18x26 ( (Mrs. Goodmans - 95.95)
24x30 (Walmart - 34.97)
16x32 (The Cake Studio - 130.00)

I was wondering what your general areas take is on what is considered a full sheet cake? I am getting some education here, I was always under the impression that the following were the standard: (now I am questioning that)

9x13 = 1/4 sheet
11x15 = 1/3 sheet
12x18 = 1/2 sheet
2 -12x18 = full sheet

I'd be interested in seeing what others have found out on this....

I would like to know the same thing. You beat me to the post.

Well the heat here must be frying my poor brain......I have been thinking all day long that a 12x18 is 18x24...... I have changed the post to the correct size......I apologize!

But still the same question......what does your area of the country consider a full sheet cake?

I find it helpful to think in terms of volume.

OK here in Lawton,OK at Johnson's Bakery
The Full sheet is 16x 24 & sells at $63.50

and at wal-mart they say they dont know what size a full is but it feeds a 100 people and sells for $34.97