Free MCAT Prep (MCAT practice)
MCAT practice questions across the sciences and CARS, written to test mechanism-level understanding rather than recall. Full explanations connect each answer back to the underlying physiology, chemistry, or reasoning principle.
Start free MCAT prep: 3,481 questions with full explanations →
MCAT at a glance
| Administered by | Association of American Medical Colleges (AAMC) |
|---|---|
| Delivery | Computer-based, at test centers. |
| Total time | 6 hours 15 minutes of content time; about 7 hours 30 minutes total seated time (excluding check-in). |
| Sections | Chemical and Physical Foundations: 59 questions, 95 min. Critical Analysis and Reasoning Skills (CARS): 53 questions, 90 min. Biological and Biochemical Foundations: 59 questions, 95 min. Psychological, Social, and Biological Foundations of Behavior: 59 questions, 95 min. |
| Question types | Multiple choice. Science sections: 10 passage-based sets (4-6 questions each) + 15 independent questions. CARS: 9 passage sets (5-7 questions each). No guessing penalty. |
| Scoring | Each section scored 118-132; total score 472-528 (sum of four sections). |
| Fee | US$360 standard registration; US$145 with Fee Assistance; +US$130 international fee outside the US, Canada and US territories (2027 testing year). |
| When offered | 2027 U.S. testing runs January 15 to September 11 (about 36 dates); no testing October-December 2027. Scores release about a month after each date. |
| Retakes | Up to 3 times in one testing year, 4 times over two consecutive years, 7 times lifetime; voids and no-shows count. |
Source: Association of American Medical Colleges (AAMC), checked October 21, 2026. Fees and policies change: confirm with the official site before you register.
MCAT practice by topic
- Chemical & Physical Foundations of Biological Systems: 268 free questions
- Biological & Biochemical Foundations of Living Systems: 231 free questions
- Psychological, Social & Biological Foundations of Behavior: 179 free questions
- Critical Analysis & Reasoning Skills: 135 free questions
How do I study for the MCAT?
Content review alone fails — the MCAT rewards applied reasoning. Alternate content blocks with question practice from day one: KomFi gives you 3,481 MCAT practice questions with mechanism-level explanations, flashcards for the high-yield facts, and mock exams for stamina.
Is the MCAT harder than the GMAT or LSAT?
It is a different kind of hard: more content volume than any other graduate admissions exam, layered with passage-based reasoning. The candidates who win treat it like training — daily reps, honest accuracy tracking, and ruthless review of misses.
Where can I practice MCAT questions for free?
KomFi publishes free MCAT practice questions with full passage structure. KomFi Basic includes 50 MCAT questions every week, explanations, introductory flashcards, and progress tracking. KomFi Pro unlocks the complete bank and full flashcard deck.
Free MCAT practice questions
- An electrophysiologist observes a neuron at its resting… Which ion is primarily responsible for this…
- Which organelle would you expect to be exceptionally well-developed in these cells?
- A researcher discovers that a population of bacteria survives exposure to an antibiotic because a few…
- What genetic term describes a single gene influencing multiple seemingly unrelated traits?
- In the human ear, sound waves cause fluid in the cochlea to… Which cells are responsible for converting these…
- Which structure is most likely dysfunctional?
- A scientist is tracking the movement of a secreted protein. If the protein has just left the 'trans' face of…
- Which molecule acts as a 'fluidity buffer' in animal cell membranes?
- A patient is admitted to the emergency department with a… How does this patient's O_2 saturation at a tissue…
- In the lung alveoli, the P_CO_2 is relatively low and the… How do these conditions facilitate the function of…
- Which equation correctly illustrates the chemical basis for the 'acid' component of this shift?
- What is the expected position of their oxygen-hemoglobin dissociation curve relative to the standard?
- A researcher is studying two genes that are located very… This phenomenon is known as:
- Which observation correctly explains the different O_2 binding behaviors?
- Which of the following changes would result in a decrease in the P_50 value of hemoglobin?
- A molecule moves into a cell against its concentration… This process is best described as:
- Which of the following describes the immediate effect on the resting membrane potential of their neurons?
- A test cross is performed by mating an individual of dominant phenotype but unknown genotype with an…
- What is the frequency of the heterozygous genotype (2pq)?
- A sprinter finishes a 400-meter dash and has an… Which statement best describes the Bohr effect in this…
- A patient with severe dehydration is likely to exhibit which of the following physiological responses to…
- A protein signal binding to a cell surface receptor leads… What is the expected outcome of this activation?
- A population of flowers is in Hardy-Weinberg equilibrium… What is the frequency of the dominant allele (p) in…
- What is the osmolarity of the filtrate at the end of the PCT compared to the initial filtrate in Bowman's…
- During a state of severe dehydration, which of the following describes the synergistic action of ADH and…