UPDATED 11/29/24 for the GMAT Focus! I’ve now been tutoring GMAT prep students for nearly a quarter-century—since the year 2000, when I was a junior at Harvard, helping friends and family prepare for the exam.
Upon my graduation, I became a full-time, professional tutor for the Princeton Review. Shortly thereafter, I started my own private, full-time tutoring practice, McElroy Tutoring, which has continued to this day. In those 24 years I have amassed over 24,000 hours of teaching, tutoring, and test-prep experience, both in-person and via Zoom / Skype—which means that I’ve seen lots of GMAT students come and go. In other words, my sample size for measuring score improvements is pretty large for just one tutor, anecdotal as my experiences may still be.
A common answer to the question “how much can I expect my GMAT score to improve?” is “50 to 150 points.” I think that’s a reasonable answer, but let’s get into a bit more detail, because I’ve seen improvements of as much as 300 points on the GMAT...but only on the low end of scores.
Let’s start with standard deviation. According to GMAC, the standard deviation of the GMAT Focus is 88 points. This means that over \(\frac{2}{3}\) (68%) of all GMAT test-takers will score somewhere between a 465 (17%) and a 645 (88%). If you can manage to break your way out of this massive group of students, then your chances of B-school admission are much greater.
A standard deviation (SD) is a great way to predict test-score improvements, since 82% of test-takers won't improve more than 1 SD, and only 2% will improve 2 SDs or more (this means, of course, that 16% of students will improve between 1 and 2 standard deviations).
To be specific, the math tells us that
only 15.87% of students will improve their test scores more than one standard deviation, and only 2.25% of students will improve more than two standard deviations.
Second, a key principle: it’s much easier to improve low scores than it is to improve high scores. Why? It’s a question of competition. A 505 on the GMAT Focus is 28% and a 605 is 72%. A big jump, yes, but possible with 100 hours or more of prep, because you’re leapfrogging a relatively weaker portion of GMAT test-takers. I've seen plenty of students go from 500 to 650-plus for this reason.
However, a 605 on the GMAT Focus is 72%, and a 705 is 98%. It’s a smaller difference in percentiles, which might lead some to conclude that it’s an easier improvement to make, but I would disagree--in reality, it's a tougher task than is 500 to 600. The same goes for 705 to 805...it’s only a 1% differential, but you have to compete with the top 1% of GMAT test-takers, a highly competitive and intelligent bunch, which is what makes it so much harder to do.
That being said, below is my list of realistic GMAT score improvements if you are willing to put in at least 100 hours of prep, based upon your starting score.
Please keep in mind that of course some students will improve more, or less, than the improvements listed. Hence the term “realistic,” which could also be construed as “average” (for dedicated students).
205 to 475 (+270 pts) = 0% to 20% (+20)
355 to 515 (+160 pts) = 3% to 32% (+29)
445 to 585 (+140 pts) = 12% to 62% (+50)
515 to 605 (+90 pts) = 32% to 72% (+40)
585 to 645 (+60 pts) = 62% to 88% (+26)
605 to 655 (+50 pts) = 72% to 91% (+19)
655 to 705 (+50 pts) = 91% to 98% (+7)
705 to 755 (+50 pts) = 98% to 99% (+1)
755 to 785 (+30 pts) = 99% to 99%
Please note: it’s super-hard to get an 805. If you can score a 705, then you can score an 805...but it will take a lot of persistence and luck. Only about .01% of GMAT test-takers earn an 800, which is 1 out of every 10,000...and keep in mind that some of these scorers will have undisclosed extended time.
Personally, I have scored in the 700s all 6 times I've taken the GMAT (including the GMAT online), and have earned perfect scores on the SAT, ACT, and GRE—but I'm still trying for a GMAT perfect score of my own. As I’ve always said: perfection is attainable, but not maintainable!
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