A 645+ is a good gmat score. But it really depends on your goals and what school you want to go to.
A good GMAT score for top business schools is typically a 655 or higher. While most schools will accept applicants with lower gmat scores, some applicants may require 685+ to be competitive. If you don’t have a strong academic track record, you may need to get a very high score to improve your candidacy. It’s important to remember that getting a high score on the GMAT isn’t enough for admission; you must also demonstrate strong academic performance and other qualities such as leadership, teamwork, and communication skills. In addition, having a well-crafted resume and strong essays can help your chances of being accepted into the school of your choice.