GMAT

Harvard Business School
Stanford Graduate School of Business
Whart on School MassachusettsInstitute of Technology Sloan
Columbia Business School
Cornell University Johnson
Northwestern University Kellogg
New York University Stern
University of Chicago Booth
University of California Berkeley
HaasDartmouth College
TuckDuke University
FuquaYale School of Management
University of MichiganAnn Arbor Ross
Carnegie Mellon University
TepperUniversity of VirginiaDarden Georgetown UniversityMcDonoughEmory University
Goizueta University of Texas
Austin McCombs
University of North Carolina
Chapel Hill Kenan Flagler
University of Illinois Urban Champaign
Georgia Institute of Technology
Vanderbilt University Owen
Washington University in St. Louis Olin.

First of all, both CAT and GMAT have different patterns. Although, both measure a person's abilities like Quantitative and verbal, but the content differs. GMAT is an adaptive test, which means as you answer the question right, a harder question will be given to you and if you answer wrong, a question easier or equal to your last question will be given. You can move forward only if you answer the current question. Whereas, CAT is a linear test where questions are numbered and you can go back and forth anytime and choose which question you want to answer first. The verbal ability parts of both the exams are somewhat different. While GMAT has Sentence Correction, Reading Comprehensions and Critical Reasoning. CAT has some similar question types but it focuses more on grammar and vocabulary. GMAT also has Analytical Writing Assessment and Integrated Reasoning which is different from Logical Reasoning and Data Interpretation questions in CAT. So Preparing for CAT may somewhat help, but since the pattern differs you have to study according to the question type and timing of the exam. Again, GMAT requires SMART studying whereas CAT requires a lot of practice.