Understanding the HESI A2 Exam Structure
Walking into the HESI A2 exam without knowing its structure is like navigating a hospital without a floor plan — you'll waste valuable time and energy figuring out where to go. The HESI A2 (Health Education Systems, Inc. Admission Assessment) can contain up to 10 different sections, though most nursing programs only require 4 to 7 of them.
This guide gives you a complete section-by-section breakdown so you know exactly how many questions you'll face, how much time you have, and what content each section covers. Whether you're preparing for an ADN, BSN, or LPN program, this is the roadmap you need.
Quick Overview: HESI A2 Sections at a Glance
Before diving into the details, here's a high-level snapshot of every possible HESI A2 section:
| Section | Questions | Time Limit | How Common? |
|---|---|---|---|
| Mathematics | 50–55 | 50 minutes | Required by almost all programs |
| Reading Comprehension | 47–50 | 60 minutes | Required by almost all programs |
| Vocabulary | 50 | 50 minutes | Required by almost all programs |
| Grammar | 50 | 50 minutes | Required by almost all programs |
| Anatomy & Physiology | 25–30 | 25 minutes | Required by most BSN programs |
| Biology | 25–30 | 25 minutes | Frequently required |
| Chemistry | 25–30 | 25 minutes | Frequently required |
| Physics | 25 | 25 minutes | Rarely required |
| Critical Thinking | 30 | Varies | Occasionally required |
| Learning Style | 14 | N/A | Informational only (unscored) |
Important: Each section may include approximately 5 unscored "pilot" questions that Elsevier uses for research purposes. You won't know which ones they are, so treat every question as if it counts.
The "Core Four" Sections (Required by Nearly Every Program)
1. Mathematics — 50–55 Questions | 50 Minutes
The math section tests your ability to perform calculations you'll use daily in nursing — from dosage calculations to unit conversions. An on-screen calculator is provided, but personal calculators are not allowed.
What's tested:
- Basic operations (addition, subtraction, multiplication, division)
- Fractions, decimals, and percentages
- Ratios and proportions
- Unit conversions (metric ↔ household, temperature, time)
- Dosage calculations
- Roman numerals
- Military (24-hour) time
- Basic algebra and word problems
Scoring tip: Most questions are multiple choice, but expect a few fill-in-the-blank problems. Double-check your decimal placement — it's the #1 source of careless errors.
2. Reading Comprehension — 47–50 Questions | 60 Minutes
This section evaluates your ability to understand, analyze, and interpret written passages — a skill that's critical for reading medical charts, research papers, and patient instructions.
What's tested:
- Identifying the main idea and supporting details
- Making logical inferences
- Determining the author's purpose and tone
- Understanding context clues for unfamiliar words
- Distinguishing fact from opinion
- Drawing valid conclusions from passages
Scoring tip: Read the questions before the passage so you know what to look for. This saves significant time.
3. Vocabulary & General Knowledge — 50 Questions | 50 Minutes
This section tests your understanding of words commonly used in healthcare and everyday English. It goes beyond simple definitions — you need to understand how words are used in context.
What's tested:
- Medical terminology (prefixes, suffixes, root words)
- General vocabulary used in healthcare settings
- Context-based word meaning
- Synonyms and antonyms
- Word parts and their meanings (e.g., "brady-" = slow, "-itis" = inflammation)
Scoring tip: If you don't know a word, break it apart. Medical terms are built from Latin and Greek roots — learning 50 key roots can help you decode hundreds of terms.
4. Grammar — 50 Questions | 50 Minutes
Proper grammar is essential for clear medical documentation and patient communication. This section tests your understanding of English language rules.
What's tested:
- Parts of speech (nouns, verbs, adjectives, adverbs)
- Subject-verb agreement
- Pronoun-antecedent agreement
- Commonly confused words (affect/effect, their/there/they're)
- Sentence structure and fragments
- Punctuation and capitalization
- Active vs. passive voice
- Comma usage and splices
Scoring tip: Read each answer choice carefully — wrong answers often sound correct at first glance. Trust the grammar rules, not your ear.
Science Sections (Required by Many Programs)
5. Anatomy & Physiology — 25–30 Questions | 25 Minutes
A&P is the section that scares students the most, but it's also the most directly relevant to nursing. You need a solid understanding of body systems and how they work together.
What's tested:
- Skeletal, muscular, and integumentary systems
- Cardiovascular and respiratory systems
- Nervous and endocrine systems
- Digestive and urinary systems
- Reproductive and lymphatic systems
- Organ functions and locations
- Homeostasis and feedback mechanisms
Scoring tip: Focus on function over memorization. Understanding why a body system works a certain way helps you answer application questions, not just recall questions.
6. Biology — 25–30 Questions | 25 Minutes
Biology tests your understanding of living organisms at the cellular and molecular level — foundational knowledge for pharmacology and pathophysiology courses later in nursing school.
What's tested:
- Cell structure and function (organelles, membranes)
- Cellular respiration and photosynthesis
- DNA, RNA, and protein synthesis
- Genetics (dominant/recessive traits, Punnett squares)
- Mitosis and meiosis
- Biological molecules (carbohydrates, lipids, proteins, nucleic acids)
- Classification of organisms
Scoring tip: Don't try to memorize everything. Focus on the processes — if you understand how cellular respiration works step-by-step, you can answer most questions about it.
7. Chemistry — 25–30 Questions | 25 Minutes
Chemistry knowledge is essential for understanding medications, IV solutions, and acid-base balance. This section tests foundational concepts, not advanced chemistry.
What's tested:
- Atomic structure (protons, neutrons, electrons)
- The periodic table (groups, periods, trends)
- Chemical bonds (ionic, covalent, hydrogen)
- Chemical reactions and balancing equations
- Acids, bases, and pH scale
- States of matter and phase changes
- Solutions, concentrations, and dilutions
- Molar mass and stoichiometry basics
Scoring tip: Memorize the first 20 elements and their properties. Most HESI A2 chemistry questions revolve around these common elements.
Less Common Sections
8. Physics — 25 Questions | 25 Minutes
Physics is only required by a handful of programs, but if your school mandates it, you need a basic understanding of physical laws and principles.
What's tested:
- Newton's laws of motion
- Force, mass, and acceleration
- Energy (kinetic, potential, conservation)
- Waves and sound
- Electricity and circuits
- Simple machines and mechanical advantage
- Gravity and projectile motion
9. Critical Thinking — 30 Questions | Time Varies
This section evaluates your ability to analyze situations, evaluate evidence, and make logical decisions — skills that are fundamental to clinical nursing practice.
10. Learning Style Assessment — 14 Questions | Unscored
This brief questionnaire identifies your learning preferences (visual, auditory, kinesthetic, or read/write). It's completely unscored and has no bearing on your admission. Answer honestly — the results may actually help you study more effectively.
Total Exam Time: What to Expect
Your total exam time depends on which sections your program requires. Here are common configurations:
- Core Four only: ~3.5 hours (Math + Reading + Vocabulary + Grammar)
- Core Four + Sciences: ~4.5–5 hours (add A&P, Biology, Chemistry)
- Full exam (all sections): ~5.5–6 hours
Most testing centers allow short breaks between sections, but policies vary. Ask your testing center about break rules before exam day.
Which Sections Does YOUR Program Require?
This is the most important step in your preparation: contact your nursing program's admissions office and ask exactly which HESI A2 sections they require. Don't assume — requirements vary dramatically even between programs at the same school.
Here's a general guide:
- ADN (Associate) programs: Usually require the Core Four, sometimes A&P and Biology
- BSN (Bachelor's) programs: Typically require the Core Four plus 2–3 science sections
- LPN programs: Usually require only the Core Four
- Accelerated BSN programs: May require all science sections plus Critical Thinking
Section-by-Section Study Strategy
Now that you understand the structure, here's how to allocate your study time effectively:
- Identify your required sections — Don't waste time on Physics if your program doesn't test it
- Take a diagnostic test — Use practice tests to identify your weakest sections
- Allocate 60% of study time to weak areas — Improving a 65% to 80% is easier (and more impactful) than improving a 90% to 95%
- Use the right study tools — Flashcards for vocabulary, practice problems for math, diagrams for A&P
- Simulate test conditions — Practice with time limits to build your pacing skills
Common Questions About HESI A2 Sections
Can I take sections on different days?
This depends entirely on your testing center and nursing program. Some allow split testing across multiple days, while others require all sections in a single sitting. Check with your program.
Are the sections adaptive?
No. Unlike the NCLEX, the HESI A2 is not a computer-adaptive test. Every student receives the same difficulty level of questions within each section.
Can I skip questions and come back?
Yes, within each section you can typically navigate back to previous questions. However, once you submit a section and move to the next, you cannot return to it.
What score do I need?
Most programs require a minimum of 75–80% per section, though competitive programs often look for 85%+. Check our detailed guide on HESI A2 passing scores for program-specific requirements.
Start Preparing With Confidence
Understanding the HESI A2 exam structure is the first step toward a high score. Now that you know exactly what each section contains, how many questions you'll face, and how much time you have, you can build a focused study plan that targets the sections that matter most for your program.
Ready to practice? Our platform includes 1,098+ practice questions across all major HESI A2 sections, plus 400+ flashcards and comprehensive study guides. Every question includes detailed explanations so you don't just learn the answer — you understand the concept.