In my department, the average thesis weighs in somewhere around 150 pages, with acceptable theses anywhere from 120 and up. A thesis that is 100 pages will raise eyebrows. One that tips the scales at 300 makes committees groan. I don't know of anyone in my generation that has graduated from my department with a two-volume thesis (once you go over 500 pages you have to bind it into two volumes). According to the deposit office, the largest in recent years at LargeU checked in at 1200 pages. It was a Communication major's.
The size of the thesis causes many grad students angst. I kept a page count as I went, but I wasn't terribly concerned with length (but that might have been because after I compiled my published first-authors, I was already over 80 pages).
And for the record, mine clocked in just at 200 pages.
I think worrying about thesis length is silly, particularly in the grand scheme of graduate school. But you would be amazed at how often I've been asked, "how long was yours?"
Does size matter in your department?
