Hardest AP Classes Ranked by Workload
The hardest AP classes by workload include Physics C, Chemistry, Calculus BC, US History, and Biology. See the ranking, why each is tough, and how to prepare.
The hardest AP classes by workload are generally AP Physics C (Mechanics and E&M), AP Chemistry, AP Calculus BC, AP US History, and AP Biology. They combine heavy weekly homework, cumulative content, and exams that demand real problem-solving or extensive writing rather than recall.
Difficulty is personal, though. A student who loves math may find Calculus BC easier than APUSH. This ranking reflects what we see across many students: total weekly time, conceptual demand, and how unforgiving the exam is.
How we ranked the hardest AP classes
We weighed four factors:
- Weekly workload — problem sets, reading, labs, and essays.
- Prerequisite load — how much prior knowledge the course assumes.
- Cumulative structure — whether falling behind in one unit sinks the next.
- Exam demand — multi-step problems, long essays, or both.
We deliberately did not rank by published score distributions alone, since those reflect who takes a course as much as how hard it is.
The hardest AP classes, ranked
| Rank | Course | Main source of difficulty |
|---|---|---|
| 1 | AP Physics C: Electricity and Magnetism | Abstract concepts plus calculus-based problem solving |
| 2 | AP Physics C: Mechanics | Calculus applied to physical systems |
| 3 | AP Chemistry | Cumulative, math-heavy, lab-intensive |
| 4 | AP Calculus BC | Fast pace; AB content plus series, parametrics, polar |
| 5 | AP US History | Massive reading load and three essay formats |
| 6 | AP Biology | Volume of content plus experimental reasoning |
| 7 | AP English Literature | Close reading and timed analytical essays |
| 8 | AP English Language | Rhetorical analysis and argument writing under time pressure |
| 9 | AP European History | Dense content and DBQ/LEQ writing |
| 10 | AP Physics 1 | Conceptual reasoning that trips up strong math students |
Why is AP Physics C so hard?
Both Physics C courses use calculus to model physical systems, and many students take them while still learning calculus. E&M is widely considered the tougher of the two because fields, flux, and induction are abstract and hard to visualize.
If you are choosing between physics courses, read AP Physics 1 vs AP Physics C.
Why is AP Chemistry so demanding?
AP Chemistry stacks every unit on the last. Stoichiometry feeds into equilibrium, which feeds into acids and bases, which feeds into thermodynamics and electrochemistry. Add labs and frequent calculations, and the weekly load is significant.
Our deep dive Is AP Chem hard? covers which units cause the most trouble.
Is AP Calculus BC harder than AB?
Yes, primarily because of pace. BC covers all of AB plus additional topics, including infinite series, parametric and polar functions, and more integration techniques, in the same school year. See Is AP Calc BC hard? and AP Calculus AB vs BC.
Why does APUSH feel like so much work?
AP US History has one of the heaviest reading loads of any AP. The exam requires short-answer responses, a document-based question, and a long essay, so you need both content knowledge and historical writing skills. Read Is APUSH hard? for a full breakdown.
Is AP Biology harder than AP Chemistry?
They are hard in different ways. AP Bio has more content to learn and asks you to analyze experiments and data. AP Chem involves more math and more cumulative problem solving. Students who prefer memorization plus reasoning often find Bio more manageable; students who like quantitative work often prefer Chem.
Hard because of workload vs. hard because of concepts
| Type of hard | Courses | Best strategy |
|---|---|---|
| Workload-heavy | APUSH, AP Biology, AP European History | Consistent daily reading and spaced review |
| Concept-heavy | AP Physics C, AP Physics 1 | Work problems, explain reasoning aloud |
| Both | AP Chemistry, AP Calculus BC | Daily practice and never letting a unit slide |
| Skill-heavy | AP English Language, AP English Literature | Frequent timed writing with feedback |
Should you take the hardest AP classes?
Take a hard AP when it aligns with your interests or intended major and you have the prerequisites. A future engineer benefits from Calculus BC and Physics C; a future history major benefits more from APUSH and European History.
Avoid stacking three or four of the hardest courses in a single year unless you have a proven track record. Our guide How many AP classes should I take? can help you calibrate.
How to survive the hardest AP classes
- Preview before class. Ten minutes skimming the next section makes lectures stick.
- Do problems daily, not in weekend marathons.
- Fix confusion within 48 hours — ask your teacher or a tutor before it compounds.
- Practice released free-response questions with official scoring guidelines from AP Central.
- Estimate your score after practice tests using the AP score calculator, including AP Physics C: E&M and AP Chemistry.
What should you do if you are falling behind in a hard AP?
Falling behind in a cumulative course is common, and it is recoverable if you act quickly.
- Identify the exact gap. Is it one unit, a skill like algebra, or simply time management? Vague worry is harder to fix than a specific problem.
- Talk to your teacher this week. Ask which topics matter most for upcoming units and whether retakes or corrections are available.
- Rebuild the foundation first. In Chemistry or Calculus, patching the earlier unit usually fixes the current one.
- Protect daily practice time. Even 30 focused minutes a day beats a three-hour weekend cram.
- Get outside help early, before a low quarter grade locks in.
Dropping a course should be a last resort and a conversation with your counselor, since schedule changes can affect how colleges read your transcript.
How Ivystar can help
The hardest APs are where expert support pays off most. In AP Exam Prep, tutors from schools like MIT, Harvard, and Cornell work through problem sets and exam strategy with you — on average, our students improve one letter grade. Book a free 20-minute strategy call to make your toughest class manageable.
Frequently asked questions
What is the hardest AP class?+
AP Physics C: Electricity and Magnetism is often considered the hardest because it pairs abstract concepts with calculus-based problem solving. AP Chemistry and AP Calculus BC are close behind.
Is AP Chemistry harder than AP Biology?+
It depends on your strengths. Chemistry is more math-heavy and cumulative, while Biology has more content to learn and more experimental analysis.
How many hard AP classes should I take at once?+
Most strong students handle one or two of the hardest APs per year. Taking more is possible but requires excellent time management and a lighter load elsewhere.
Do colleges prefer hard AP classes?+
Colleges value rigor in context, especially in subjects related to your intended major. A hard AP with a strong grade signals readiness for college coursework.
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