HESI A2 Hardest Sections Ranked: A Data-Driven Study Strategy for 2026
The HESI A2 (Health Education Systems, Inc. Admission Assessment) is the gateway to nursing school for hundreds of thousands of applicants every year. But not all sections are created equal — some are dramatically harder than others, and knowing where to focus your limited study time can mean the difference between admission and rejection.
According to student surveys, the average cumulative HESI A2 score on first attempts falls between 60–69%, and many students need to retake the exam to reach their program's minimum.
This guide ranks every HESI A2 section from hardest to easiest based on student pass rates, nursing school admission data, and tutor feedback, then gives you a targeted study plan for each one.
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How the HESI A2 Sections Are Scored
Before diving into the rankings, here's what you need to know about HESI A2 scoring:
| Detail | Info |
|---|---|
| Score Range | 0–100% per section (converted score) |
| Most Common Minimum | 75%–85% depending on the nursing program |
| Competitive Score | 90%+ on each section |
| Sections Tested | Varies by school (typically 4–7 sections) |
| Time Limit | ~4 hours total for all sections |
| Retake Policy | Once every 60 days, up to 3x per year |
Critical note: Each nursing program chooses which sections to require. Always check your target school's specific requirements before registering.
The HESI A2 Sections Ranked by Difficulty
#1 — Anatomy & Physiology (Hardest)
Why it's the hardest: This section requires you to know 11 body systems in detail — their structures, functions, and interactions. Unlike other sections that test skills you've used your whole life (reading, grammar, basic math), A&P demands specialized knowledge that most students haven't studied since high school biology, if at all.
| A&P Quick Facts | Details |
|---|---|
| Questions | 30 |
| Topics | 11 body systems, cell biology, histology, directional terms |
| Average Student Score | 72%–78% |
| What Makes It Hard | Volume of memorization, interconnected systems |
Key topics to master:
- Cardiovascular system — Heart chambers, blood flow pathway, major vessels
- Endocrine system — Glands, hormones, feedback loops
- Nervous system — CNS vs. PNS, neuron structure, reflex arcs
- Musculoskeletal system — Major bones, muscle types, joint classifications
- Directional terminology — Superior/inferior, medial/lateral, proximal/distal
Study strategy:
- Start with directional terms and body planes — these appear on nearly every HESI A2
- Focus on high-yield systems: cardiovascular, endocrine, and nervous
- Use visual diagrams rather than text-only study — anatomy is inherently visual
- Learn at the "overview" level, not the "medical school" level — know which hormones come from the pituitary gland, but you don't need to memorize every releasing factor
#2 — Chemistry
Why it's hard: Many nursing applicants haven't taken chemistry since high school, and the HESI A2 chemistry section requires understanding of concepts like the periodic table, chemical reactions, solutions, and biochemistry basics that feel unfamiliar after years away.
| Chemistry Quick Facts | Details |
|---|---|
| Questions | 30 |
| Topics | Atomic structure, periodic table, reactions, solutions, biochemistry |
| Average Student Score | 74%–80% |
| What Makes It Hard | Abstract concepts, formula memorization, long gap since last chemistry class |
Key topics to master:
- Atomic structure — Protons, neutrons, electrons, electron shells
- Periodic table — Groups, periods, element properties
- Chemical bonds — Ionic vs. covalent vs. hydrogen bonds
- Solutions — Concentration, dilution, pH scale, acids/bases
- Biochemistry basics — Carbohydrates, lipids, proteins, nucleic acids
Study strategy:
- Start with the periodic table structure — understanding groups and periods unlocks many questions
- Memorize the pH scale (0–14) and what makes acids vs. bases
- Practice balancing simple chemical equations
- Focus on biochemistry basics since these connect directly to nursing coursework
#3 — Mathematics
Why it's moderately hard: The math itself is basic (no calculus, no advanced algebra), but the HESI A2 math section is harder than most students expect because it tests dosage calculations, unit conversions, fractions, decimals, and ratios — all without notes. Many students make careless errors under time pressure.
| Math Quick Facts | Details |
|---|---|
| Questions | 55 |
| Topics | Basic operations, fractions, decimals, ratios, conversions, dosage calculations |
| Average Student Score | 80%–86% |
| What Makes It Hard | No personal calculator allowed (on-screen only), conversion memorization, time pressure |
Key topics to master:
- Fractions — Adding, subtracting, multiplying, dividing, converting to decimals
- Ratios and proportions — Cross-multiplication, ratio word problems
- Unit conversions — Metric ↔ household measurements, temperature conversions
- Percentages — Finding percentages, percentage increase/decrease
- Roman numerals — Used in medical prescriptions and dosage orders
Study strategy:
- Memorize conversion factors: 1 kg = 2.2 lbs, 1 inch = 2.54 cm, 1 oz = 30 mL
- Practice fraction operations daily — these are the most common error source
- Work through ratio/proportion problems using cross-multiplication
- Practice with the on-screen calculator style (don't rely on your phone's calculator)
#4 — Reading Comprehension
Why it's moderate: Most students do reasonably well here because reading skills transfer from everyday life. However, the passages are dense medical/health topics, and the questions test inference and critical analysis rather than simple recall.
| Reading Quick Facts | Details |
|---|---|
| Questions | 55 |
| Topics | Main idea, supporting details, inference, author's purpose, vocabulary in context |
| Average Student Score | 84%–90% |
| What Makes It Hard | Dense medical passages, inference questions, time pressure |
Study strategy:
- Read the questions before the passage — know what you're looking for
- Practice identifying main ideas vs. supporting details
- For inference questions, choose the answer supported by the text, not your outside knowledge
- Read health-related articles regularly to build comfort with medical terminology
#5 — Vocabulary & General Knowledge
Why it's easier: This section tests everyday English vocabulary plus medical/healthcare terms. Students who read regularly tend to score well, and the vocabulary is learnable through flashcard-style study.
| Vocabulary Quick Facts | Details |
|---|---|
| Questions | 55 |
| Topics | Common English words, medical terminology, words used in healthcare settings |
| Average Student Score | 86%–92% |
| What Makes It Hard | Medical terminology can be unfamiliar |
Study strategy:
- Learn common medical prefixes (hyper-, hypo-, brady-, tachy-) and suffixes (-itis, -ectomy, -ology)
- Use flashcards for the top 200 HESI A2 vocabulary words
- Study words in context rather than isolated definitions
- Focus on words commonly used in healthcare settings
#6 — Grammar (Easiest)
Why it's the easiest: Grammar rules are finite, and most students have a working knowledge from years of English classes. The questions test standard grammar conventions that are straightforward to review.
| Grammar Quick Facts | Details |
|---|---|
| Questions | 55 |
| Topics | Parts of speech, sentence structure, punctuation, common errors |
| Average Student Score | 88%–94% |
| What Makes It Hard | Tricky subject-verb agreement, comma splice questions |
Study strategy:
- Review the top 10 grammar rules: subject-verb agreement, pronoun-antecedent agreement, comma rules, semicolons, apostrophes
- Practice identifying sentence fragments and run-on sentences
- Focus on commonly confused words (affect/effect, their/there/they're, then/than)
- Take a quick grammar diagnostic to find your specific weak spots
Recommended Study Timeline by Section
| Week | Focus | Hours/Week | Priority |
|---|---|---|---|
| Weeks 1–2 | Anatomy & Physiology | 10–12 hours | Highest |
| Weeks 3–4 | Chemistry | 8–10 hours | High |
| Week 5 | Mathematics | 6–8 hours | Medium |
| Week 6 | Reading + Vocabulary + Grammar | 6–8 hours | Lower |
| Week 7 | Full practice tests + weak areas | 8–10 hours | Review |
| Week 8 | Final review + rest before exam | 4–6 hours | Review |
Total recommended study time: 50–70 hours over 6–8 weeks
Access Your FREE HESI A2 Study Materials
Our comprehensive study guide covers all HESI A2 sections with:
- Detailed content explanations for every section
- Practice questions with full answer explanations
- AI-powered study help for instant topic explanations
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5 Common Mistakes That Cost Students Points
1. Studying All Sections Equally
Students often split their time evenly across all sections. This is a mistake. A&P and Chemistry need 2–3x more study time than Grammar or Vocabulary.
2. Ignoring the On-Screen Calculator
The HESI A2 provides an on-screen calculator for math — but many students never practice with one. The interface is different from your phone's calculator. Practice with it beforehand.
3. Cramming Anatomy & Physiology
A&P has too much material to cram in a few days. You need spaced repetition over at least 2–3 weeks to retain 11 body systems.
4. Skipping Practice Tests
Practice tests reveal your actual weak spots and build test-day stamina. Take at least 2–3 full-length practice tests before your real exam.
5. Not Checking School-Specific Requirements
Some schools only require 4 sections. Others require 7. Some need an 80% minimum. Others want 90%+. Studying for sections your school doesn't require wastes valuable time.
Score Requirements by Nursing Program Type
| Program Type | Typical Minimum Score | Competitive Score |
|---|---|---|
| ADN (Associate Degree) | 75%–80% per section | 85%+ |
| BSN (Bachelor's Degree) | 80%–85% per section | 90%+ |
| Accelerated BSN | 80%–90% per section | 92%+ |
| MSN Direct Entry | 85%–90% per section | 95%+ |
Pro tip: Aim for at least 5–10 points above your program's minimum. Admission is competitive, and higher HESI A2 scores can compensate for a lower GPA.
Start Studying the Hardest Sections First
Don't let Anatomy & Physiology or Chemistry catch you off guard. Our free study guide walks you through every section with targeted lessons and practice questions. Start with the hardest sections first and build your confidence.
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Official Resources
- Elsevier HESI A2 Information — Official exam registration and details
- HESI A2 Practice Tests — Official practice tests from Elsevier