We’ve all faced those head-scratching, nerve-wracking exams that make us wonder if we’ve signed up for a real-life IQ showdown.
Speaking of academic challenges, we all know students and graduates in the US are no strangers to them. From medical licensing exams that can shape entire careers to standardized tests assessing graduate school readiness, the spectrum of challenges is wide and diverse.
But what makes these exams tough, and how can we objectively compare them? If you’re curious like us, we’ve collected data on prep time, exam duration, pass rates, and yearly candidates to find the most challenging US exams.
Here are the hardest exams in the United States:
| Examination | Preparation hours | Duration Time | Pass rate % | Candidates per year |
|---|---|---|---|---|
| United States Medical Licensing Examination (USMLE) | 200-400h per each step (3 steps) | step 1 – 8 hours step 2 CK – 9 hours step 3 – two-day exam 16 hours |
Above 90% for Step 1, Step 2 CK, & Step 2 CS, and around 85-95% for Step 3 | More than 50,000 |
| Bar Exam | 500-800h | 2 days, 6h each day | 60-75% | 20,000-40,000 or more |
| Certified Public Accountant (CPA) Exam | 300-400h | 4 sections/ 6h each 16 hours in total |
45-60% | 70,000-80,000 |
| Chartered Financial Analyst (CFA) Exam | 300-400h | single-day test for each level, split into morning and afternoon sessions, about 3 hours each. | 40-45% | 100,000- 150,000 |
| Graduate Record Examination (GRE) | 50-100h | 3h and 45min | No pass/fail Scores To achieve: in verbal (130-170), quantitative (130-170), and writing (0-6) used by universities for admissions. |
More than 350,000 |
| National Council Licensure Examination (NCLEX) | 100-200h | Up to 5h | 85% | Around 190,000 |
| Multistate Professional Responsibility Examination (MPRE) | 50-100h | 2h | 85% | 30,000-40,000 |
| Advanced Placement (AP) Exams | 50-100h | 2h to 3h | 50-70% | 4 Million |
| United States Medical College Admission Test (MCAT) | 30-500h | 7.5h | No pass/fail; scores range from 118-132 per section. | More than 85,000 |
| Graduate Management Admission Test (GMAT) | 100-200h | 3h & 7min | No pass/fail | More than 100,000 |
1. The United States Medical Licensing Examination (USMLE)
The United States Medical Licensing Examination (USMLE) takes the top spot as the most challenging exam in the US, with an average preparation time ranging from 200 to 400 hours for each of its three steps. Yes, you read that right, medical graduates aiming to practice in the United States undergo the USMLE in three steps.
Step 1, usually taken at the end of the second year of medical school, tests basic science knowledge in an 8-hour exam. Step 2 assesses medical knowledge and clinical skills in a 9-hour test during the fourth year. Step 3 focuses on patient management in ambulatory settings and spans 2 days, totaling 16 hours.
Despite relatively high pass rates (above 90% for Step 1, Step 2, and around 85-95% for Step 3), candidates invest four years in medical school and their first year of residency to prepare for this exam. Dedication is an understatement!
2. The Uniform Bar Examination (UBE)
The second hardest exam in the United States is the Uniform Bar Examination (UBE), required for aspiring lawyers to practice in the country.
The Uniform Bar Examination (UBE) is a legal showdown lasting 12 hours, spread across two days, with an average pass rate of 60%-75%. It challenges candidates with the Multistate Essay Examination (MEE), two Multistate Performance Test (MPT) tasks, and the Multistate Bar Examination (MBE).
While 36 states or jurisdictions in the U.S. have adopted the UBE, some have their own versions. For instance, the California Bar Exam is notorious for its toughness, with a significantly low pass rate (51.5%) compared to other states in 2023.
3. The Uniform Certified Public Accountant (CPA) Exam
The Uniform Certified Public Accountant (CPA) Exam is the financial world’s ultimate challenge, demanding an investment of 300-400 hours for preparation.
Spanning four sections—Auditing and Attestation (AUD), Business Environment and Concepts (BEC), Financial Accounting and Reporting (FAR), and Regulation (REG)—this computer-based exam takes a grueling 16 hours in total.
The CPA Exam uses a scoring system from 0 to 99, and candidates need a minimum score of 75 to pass each of its four sections. Among the four sections, FAR holds a notorious reputation as the toughest, consistently boasting the lowest pass rates. Some even joke that CPA stands for “Couldn’t Pass Again”.
4. The Chartered Financial Analyst (CFA) Exam
The CFA Exam is another rigorous assessment taken by finance professionals seeking career advancement. It includes three levels, each needing substantial preparation, totaling 300-400 hours. Each level is a single-day test, split into morning and afternoon sessions, lasting about 3 hours each.
Level I is more difficult to pass, with a historical rate of around 41% and dropping to 37% recently. Levels II and III are considered more demanding due to higher knowledge requirements, but better preparation leads to higher pass rates, such as 44% for Level II and 47% for Level III in August 2023.
On average, more than 100,000 to 150,000 candidates take this exam annually, and it typically takes over four years to complete the full program. If you’re eyeing a career as a portfolio manager, becoming a CFA charter holder can pay off quite well, with an average base salary of $126,000 and a total compensation package of around $177,000. So, all that studying might just be worth it in the end.
5. Graduate Record Examination (GRE)
The fifth most difficult exam in the US is the Graduate Record Examination (GRE), a significant challenge for over 350,000 candidates every year. This 3-hour and 45-minute computer-adaptive test assesses skills in Analytical Writing, Quantitative, and Verbal areas.
Unlike pass/fail exams, the GRE assigns scaled scores between 130 and 170 for verbal and quantitative sections, and a writing score from 0 to 6. What makes the GRE unique is its adaptability; the questions get tougher as you perform better.
Your goal? To achieve a high percentile rank, showing how you stack up against other test-takers. This exam opens doors to graduate programs in diverse fields, including business and psychology. Some universities even offer financial incentives for students with high GRE scores.
| Great news for GRE test-takers: starting September 22, 2023, the Quantitative and Verbal Reasoning sections are shorter, with 27 questions each. The test duration has been reduced to just 1 hour and 58 minutes. Don’t be surprised if we rank this exam lower in the near future. 🤭 |
6. National Council Licensure Examination (NCLEX)
The National Council Licensure Examination (NCLEX) is a rigorous exam taken by around 190,000 candidates in the US each year, including NCLEX-RN for registered nurses and NCLEX-PN for practical/vocational nurses.
Each exam lasts up to 5 hours and includes a minimum and maximum of questions to be answered. For the NCLEX-RN, candidates have to answer 75 to 145 questions, whereas NCLEX-PN takers have to answer 85 to 205 questions.
The NCLEX’s comprehensive content, critical thinking focus, and computerized adaptive format demand thorough preparation, 100 to 200 hours to be exact. With an 85% pass rate, success isn’t just about knowledge but also handling diverse question types and clinical decision-making.
7. Multistate Professional Responsibility Examination (MPRE)
The Multistate Professional Responsibility Examination (MPRE) is a crucial two-hour, 60-question multiple-choice test taken by approximately 30,000-40,000 candidates annually. It is a prerequisite for admission to most U.S. bars, although Wisconsin and Puerto Rico have different requirements.
This exam, developed by NCBE, evaluates candidates on ethics and professional responsibility. Unlike the bar exam, which allows room for explanation and reasoning, the MPRE is a more straightforward, rule-based test.
While some find it fairly less difficult in comparison to the bar, others find it challenging due to its black-and-white nature, particularly if they struggle with multiple-choice exams. Success on the MPRE is essential either before or after passing your state’s bar exam, making it a crucial step in the journey to becoming a lawyer.
8. Advanced Placement (AP) Exams
AP exams, also known as Advanced Placement exams, are like a rite of passage for 4 million U.S. high school students each year. Administered by the College Board, these tests are a common choice for those who’ve tackled advanced coursework, often through AP classes.
There are 38 AP exams available in a wide range of subjects, including AP Calculus, AP Biology, AP English Literature, AP U.S. History, and more. They include both multiple-choice and free-response questions, and the duration varies by subject.
Your score, which ranges from 1 to 5, can earn you college credit if you achieve a 3 or higher. However, AP exams are known for their difficulty, with pass rates typically ranging from 50% to 70%.
A Quora user provides a great explanation of its difficulty:
| “A.P. classes are hard because they are college-level classes taught in high school. The best way to do well is to accelerate your development so that you are the equivalent of a college freshman while a junior or senior in high school.” |
9. United States Medical College Admission Test (MCAT)
The United States Medical College Admission Test (MCAT) is a crucial component of the medical school admissions process in the U.S. and Canada. With a duration of approximately 7.5 hours, including breaks, it’s a marathon of a test. Candidates invest anywhere from 30 to 500 hours to be adequately prepared.
The MCAT covers four main sections and is scored from 118 to 132 per section, totaling 472 to 528. The average candidate scores around 500, but if you’re aiming for top medical schools like Harvard, Yale, Stanford, or Johns Hopkins, the competition is fierce, with accepted students boasting median average scores in the 520s.
In 2023-2024, those who made it into U.S. MD-granting medical schools had an average total MCAT score of 511.7. Following their experience with the exam, one candidate comments:
| “It is the most challenging test I have ever taken. I studied my brains out and still didn’t feel prepared enough – I don’t think anyone really does except for the few that are truly brilliant. It takes a lot of hard work.” – Quora |
10. Graduate Management Admission Test (GMAT)
Lastly, we have the Graduate Management Admission Test (GMAT), a test undertaken by an impressive 100,000 individuals annually, especially those seeking admission to graduate business programs like MBA (Master of Business Administration).
With preparation times ranging from 100 to 200 hours, it’s a significant commitment. This standardized exam spans four sections, including analytical writing, reasoning, quantitative skills, and verbal reasoning. What sets the GMAT apart is its scoring system, ranging from 200 to 800.
Unlike traditional exams, there’s no straightforward pass or fail, but achieving a high GMAT score often opens the doors to top business schools. To put this in perspective, the average GMAT score hovers around 582, but for those aiming to secure a spot in elite business schools like Stanford, Wharton, or MIT, the competition is fierce, with admitted MBA students in 2025 averaging scores in the high 700s.