• Hello,
• A one word answer to your question could have been - LOTS. But let us see the difference under some heads which are pertinent to the preparation:
• ABOUT EXAMS : CAT is an exam conducted by IIMs for admission to the 20 IIMs and several CAT allied institutions. While CET is an exam conducted by individual state professional examination boards or universitites- such as CET of Maharashtra or CET conducted by DAVV Indore.
• LEVEL OF DIFFICULTY: CAT is the tougher of the two exams. Tough , in terms of the nature of questions asked and tough in terms of competition that you will have to face. Any aspirant for admissions to top B schools in India will write CAT, but may or may not write CET.

Hello Shashank,

CAT exam is conducted by IIMS at national levels for admissions in mba courses. And CET exam is conducted by individuals colleges or university for admission in colleges for various courses at state level. CAT stands for common admission test and CET stands for common entrance test. Example for CET exams are MH-CET, or CET conducted by DAVV in indore.

ALL the best. Hope this will helps you.