GRE vs GMAT : Which one to choose?

Globally, most of the b-schools accept GMAT or GRE for admission into MBA programs which means aspirants can take either GRE or GMAT. While GMAT (Graduate Management Admission Test) is a Computer Adaptive Test (CAT) which assesses certain analytical, writing, quantitative, verbal and reading skills of candidates in written English for use in admission to graduate, management program only, the GRE (Graduate Record Examination) is a standardized test which is an admission requirement for most graduate schools in the USA.

GMAT vs GRE structure and Scoring:
The main difference between GMAT and GRE is that the latter test is used for admissions into various graduate schools programs, while the former is only used to apply for business schools. In the GMAT exam, each individual question determines the difficulty of the next question; however, in GRE each section determines the difficulty of the next section, making both the tests computer adaptive test.

Length 3 hours 30 minutes  3 hours 45 minutes
No. of essays 1 2
MCQ questions 90 80+20 (Unscored research questions)
Sections 4 6 (Including an unscored research section)
Composite scoring 200- 800, 10 points increments 130- 170 (Verbal and Quant each) total 260- 340, 1 point increment
Application fee USD 250 USD 205
Score validity 5 years 5 years

Challenging section:
In GMAT, Maths is really excruciating and the candidate needs to have good command over grammar, but in GRE the verbal section is bit tough as it covers wide variety of vocabulary and major emphasis is on writing.

Do Business schools prefer GMAT or GRE?
GRE is the most widely accepted graduate school admissions exam and it can be used to apply to a variety of programs. The GMAT is almost used only to apply for business schools. If you are sure enough to join any business school and have no interest in other programs the it is better to go for GMAT because it will show to the b-schools that you are only committed to take admission there.