MCAT Percentiles Explained: What They Mean and Why CARS Matters

Your MCAT percentile doesn’t just reflect a number; it tells a story about where you stand among thousands of other test takers vying for spots at top American medical colleges. While the scaled score gives you a raw snapshot, the percentile rank reveals how competitive that score truly is. In this guide, we’ll break down MCAT exam percentiles by section so you can pinpoint your strengths, identify opportunities, and strategize your prep like a future physician. Whether you’re aiming for the highest MCAT score or just want to know what counts as a good MCAT score, this is your complete roadmap to understanding percentile ranks and why they matter more than you think.

I. What Are MCAT Percentiles?

MCAT percentiles represent how your score compares to those of other test takers. Rather than indicating the number of questions you got right, a percentile rank shows the percentage of examinees who scored lower than you. For instance, scoring in the 90th percentile means you performed better than 90% of all test takers from that year.

It’s important to distinguish percentiles from scaled scores or raw scores. Your MCAT raw score reflects the number of questions you answered correctly, which is then converted into a scaled score between 118 and 132 for each section. This scaled score accounts for slight differences in difficulty across test versions. However, neither raw nor scaled scores give admissions committees a full picture of your competitiveness—that’s where percentiles come in.

Percentiles are especially critical for medical school admissions. A 128 in the CARS section may mean something very different depending on how others performed that year. American medical colleges rely on percentile ranks to evaluate applicants fairly and to understand how well they perform under pressure in comparison to peers across the country. In short, knowing your percentile tells you not just how well you did, but how well you did relative to everyone else.

II. MCAT Percentiles by Section

Each section of the MCAT exam, Chemical and Physical Foundations of Biological Systems (CPBS), Biological and Biochemical Foundations of Living Systems (BBLS), Psychological, Social, and Biological Foundations of Behavior (PSBB), and Critical Analysis and Reasoning Skills (CARS), has a score range on the same 118-132 scale, but their percentile ranks can vary depending on how other test takers perform. These variations help explain why the same MCAT score ranges don’t always mean the same thing across sections.

Chemical and Physical Foundations of Biological Systems covers physics, chemistry, and biology, often showing a balanced percentile spread. A 127 here might land around the 78th percentile. Biological and Biochemical Foundations of Living Systems, focused on biology and biochemistry, tends to be slightly more competitive due to strong pre-med preparation. A 127 may fall near the 75th percentile. 

Psychological, Social, and Biological Foundations of Behavior includes psychology, sociology, and behavior-related biology. Percentiles are a bit more forgiving; scoring a 128 could place you in the low 80s percentile. CARS is the most unpredictable and often has the steepest percentile curve. Because it doesn’t rely on content knowledge, it trips up many students. A 128 in CARS may reach the 91st percentile, far higher than the same score in other sections, making it a key area for admissions impact.

III. CARS Percentiles: Why They Stand Out

The Critical Analysis and Reasoning Skills (CARS) section is unique among MCAT section scores, and not just in content. Unlike the science sections, CARS doesn’t test memorized knowledge, but rather reading comprehension, logic, and critical thinking. As a result, many students struggle with it, and the average CARS percentile tends to be lower than for CPBS, BBLS, or PSBB. This makes even moderate CARS scores more impressive in context.

Medical schools often weigh CARS more heavily because it reflects how well students might handle clinical reasoning and decision-making. The steep percentile rank curve makes every point matter significantly more.

Consider the impact:

• A 125 in CARS is the 62nd percentile, while the same score in a science section might rank lower.
• A 128 catapults you to the 90th percentile, indicating top-tier reading and reasoning skills.
• A 130 reaches the 98th percentile, a rare score that can set your application apart, even if your overall MCAT score isn’t perfect.

If you're looking for the highest return on score improvement, CARS is often the smartest target. Learn more in our guide: What is a Good CARS Score?

IV. What is a Good MCAT Percentile?

When evaluating your MCAT score, percentiles provide crucial context that raw or scaled scores alone can’t offer. A good MCAT score is generally one that places you above the median test taker, but what’s considered competitive or elite depends on your goals and target medical schools.

Here’s a general breakdown:

• 50th percentile: Around a total score of 500 and considered an average MCAT score. It may be insufficient for most MD programs.
• 75th percentile: Around 508-509. Competitive for many mid-tier schools.
• 90th percentile: Typically a 514-515. Strong candidate for top-tier programs.
• 99th percentile: Around 522-523 score range. This is elite territory, where few applicants reside.

Competitive applicants usually fall at or above the 75th percentile, especially if other application components - GPA, clinical experience, and essays - are strong. Reaching the 90th percentile and beyond often sets applicants apart at research-heavy or highly selective institutions.

Keep in mind that percentile ranks shift slightly year to year based on the performance of the overall applicant pool. A 515 one year might land at the 91st percentile, but the same score might rank slightly lower or higher depending on trends.

V. How Do MCAT Percentiles Change Year to Year?

Although the MCAT total score range has remained fixed between 472 and 528 since the exam’s redesign, percentile ranks are not static. Each year, the AAMC publishes tables of new MCAT percentiles that reflect the performance of all test takers over the prior three years. This means your percentile rank can shift slightly, even if your scaled score stays the same. For example, a score of 515 may have placed you in the 91st percentile one year, but only in the 90th percentile the next. These changes are usually small (1-2 percentile points), but they can affect how your score is interpreted by medical schools.

Several factors influence these yearly shifts. The size and composition of the test taker pool can change as more students apply to medical school. Additionally, increased access to high-quality prep materials may lead to score inflation, slightly raising the average performance. That’s why the AAMC updates percentiles annually; this ensures fairness and accuracy in evaluating applicants. In short, while your MCAT exam score is fixed, your percentile rank is dynamic, another reason it’s crucial to consult the most current data when evaluating your performance.

VI. How to Use Percentiles Strategically in Prep

Understanding MCAT exam percentiles isn’t just about interpreting your results, it’s also a powerful tool for guiding your study strategy. Percentile data helps you identify which section scores are holding you back and where improvement will most impact your competitiveness. Start by benchmarking your CARS performance. Because CARS percentiles tend to be steeper than other sections, even a small increase in your scaled score can lead to a large jump in percentile rank. For instance, moving from a 125 to a 128 could raise your percentile by nearly 30 points. This makes CARS an especially strategic target for boosting your overall standing. To build a strong CARS game plan, explore our detailed guide: How to Study for CARS MCAT Effectively.

Next, use percentile breakdowns to pinpoint your weaker sections. Are your science scores lagging behind CARS? Is PSBB bringing down your total percentile rank? Focusing on the section with the lowest percentile, not just the lowest scaled score, can help you make more meaningful improvements. By studying percentiles, you’re not just studying smarter, you’re prepping like an admissions strategist. Comprehending how MCAT score ranges translate into percentiles is essential for targeting the right sections in your prep.

VII. Tools and Tables: Understanding Your Percentile Rank

To accurately interpret your MCAT exam percentile, it’s essential to use up-to-date tools and official data. The AAMC releases an annual percentile rank table based on results from all test takers over the past three years. This table allows you to convert your scaled score for each section and your total score into a percentile that reflects your performance relative to peers.

For example, if you scored a 128 on CARS, referring to the latest percentile chart might reveal that you're in the 90th percentile for that section. These small differences matter: a 127 could be 85th percentile, while a 129 might reach 95th. Without the table, these numbers would seem flat, but with it, you gain context, strategy, and motivation.

Most MCAT exam prep platforms, including CARSBooster, provide built-in scoring analytics and historical percentile data to help benchmark your progress. Tracking your percentile movement over time gives you a dynamic view of your growth, not just in raw performance, but in how you stack up against other test takers. Incorporating these tools into your study plan turns your MCAT prep into a data-driven, outcome-focused journey.

VIII. FAQ

Q: What is a percentile rank on the MCAT?
A: It shows how you performed compared to other test takers. A 90th percentile means you scored better than 90% of examinees, giving schools context beyond your raw score.

Q: Is 90th percentile good enough for med school?
A: Yes, a 90th percentile (around 515) is strong for most med schools. It places you well above the average MCAT score and within reach of many top-tier programs.

Q: What CARS percentile is considered competitive?
A: A CARS score in the 85th percentile or higher (around 128+) is competitive. Because schools often value CARS heavily, a high percentile can strongly boost your application.

Q: Do MCAT percentiles change every year?
A: Yes, percentiles are updated annually by the AAMC. Changes are typically small, reflecting trends in test taker performance over the previous three years.

Q: What’s the average MCAT percentile overall?
A: The average is the 50th percentile, equivalent to a total score near 500-501. Scoring above this benchmark means you're outperforming most test takers.