they are both very different, and very alike. this topic has been covered countless times, so i suggest you do a search.
to sum it up... both exams cover biology, chemistry, organic chemistry, and reading comprehension.
unlike the mcat, the dat has perceputal ability and quantitative reasoning sections. the mcat however, contains physics and a writing portion..neither of which are tested on the dat.
these exams are alike as they are both standardized, computer-based exams that cover a large amount of information. mcat questions generally require critical thinking (as they are based on passages), whereas the dat questions are straightforward. however, to answer dat questions you must know DETAILS--the scope of the dat biology is very broad.
anyways, that's dat vs. mcat in a nutshell. as mentioned before, do a search and you will find countless threads on the topic... most of which turn into mcat is harder than the dat and vice-versa arguments 🙄
jb!🙂