The HESI A2 is a 170-question, multiple-choice exam that nursing programs use to evaluate applicants, and it covers a surprisingly wide range of subjects in just three hours. The good news: every section tests foundational knowledge, not advanced material. With a structured plan and the right focus areas, most students can prepare effectively in four to six weeks.
What the Exam Covers
The HESI A2 has four scored sections. Reading Comprehension (55 questions) and Vocabulary and General Knowledge (55 questions) make up the English half. Biology (30 questions) and Anatomy and Physiology (30 questions) make up the science half. Some nursing programs also require a math section with 55 questions, and an onscreen calculator is provided during that portion. You won’t need to bring your own.
Three hours is your total window, including short breaks. That sounds tight for 170 questions, but most students finish with time to spare if they don’t linger on individual items. Spending more than 90 seconds on any single question is a sign to flag it, move on, and come back.
Build a Study Schedule
A good baseline is one week per major section, which puts you at a four-week minimum. Six weeks is better if your schedule allows it, because it gives you breathing room for review and practice tests. Plan for a few focused hours each week rather than marathon cramming sessions. Spreading study time across multiple shorter sessions improves retention far more than a single eight-hour day.
A practical six-week plan looks something like this:
- Weeks 1–2: English sections (vocabulary, reading comprehension, grammar concepts)
- Week 3: Biology
- Week 4: Anatomy and Physiology
- Week 5: Math (if required by your program)
- Week 6: Full-length practice tests and targeted review of weak spots
If you only have four weeks, combine the two English sections into one week and cut the final review week down to a few days. Prioritize whichever subjects feel least familiar.
How to Study the English Sections
The Vocabulary and General Knowledge section tests words commonly used in both everyday English and healthcare settings. Flashcards are the most efficient tool here. Focus on medical root words, prefixes, and suffixes. If you know that “cardio” means heart and “itis” means inflammation, you can reason through unfamiliar terms even on test day.
Reading Comprehension questions ask you to identify main ideas, understand words in context, draw inferences, and recognize an author’s tone. These aren’t trick questions. The answers are almost always supported directly by the passage. Practice by reading a short passage, covering it up, and summarizing the main point in one sentence. If you can do that reliably, you’ll handle this section well.
Some programs include a grammar component. Key concepts to review include the difference between independent and dependent clauses, how conjunctions connect ideas, how adjectives modify nouns, and how adverbs (usually ending in “-ly”) modify verbs. You should also know what a compound sentence is: two complete thoughts joined together, each able to stand on its own. Recognizing sentence structure errors is easier once you can identify these building blocks.
What to Focus on in Biology
The biology section covers foundational cell biology, not advanced genetics or microbiology. The highest-yield topics are cellular structure, how cells get energy, and how substances move in and out of cells. Know the difference between active transport (which requires the cell to spend energy) and passive transport (which doesn’t). This distinction appears frequently.
You should also review the basics of metabolism, cellular respiration, the role of water in biological processes, and the general structure of molecules like proteins and carbohydrates. Think of this section as a refresher on what you’d cover in the first few weeks of an introductory biology course. If it’s been years since you took bio, a review book or a set of targeted flashcards focused on cell biology will go a long way.
What to Focus on in Anatomy and Physiology
This section tests your knowledge of body systems, basic anatomical terminology, and how organs work together. The human body has 11 organ systems and four basic tissue types, and you should be familiar with all of them at a high level.
Anatomical direction terms come up repeatedly. “Anterior” means toward the front of the body. “Proximal” means close to the trunk. “Optic” relates to the eye or vision. These terms aren’t complicated, but there are enough of them that they’re worth drilling with flashcards until they feel automatic.
For body systems, focus on what each one does. The integumentary system (skin) protects internal tissues, waterproofs the body, and helps regulate temperature. The muscular system produces movement through contraction, and it includes three types of muscle tissue: smooth, skeletal, and cardiac. The nervous system includes the brain and coordinates signals throughout the body. The cardiovascular system handles circulation, transporting oxygen and nutrients to tissues. Connective tissue is a broad category that includes cartilage, fat tissue, and even blood.
You don’t need to memorize every bone or muscle. Focus on understanding what each system does, which major organs belong to it, and how systems interact with each other.
Preparing for the Math Section
The math section covers arithmetic, fractions, decimals, percentages, basic algebra, and ratios and proportions. Nothing beyond what you’d encounter in a high school algebra class. The onscreen calculator handles computation, so the real challenge is setting up problems correctly rather than doing mental math.
Ratios and proportions deserve extra attention because they’re directly relevant to nursing (drug dosage calculations use them constantly) and because they tend to trip up students who haven’t practiced them recently. Work through problems that ask you to convert between fractions, decimals, and percentages until the process feels routine. If you can look at 3/4 and immediately know it’s 0.75 or 75%, you’re in good shape.
Practice Tests Make the Biggest Difference
Content review gets you familiar with the material, but timed practice tests build the speed and confidence that actually raise your score. Take at least two full-length practice exams before test day. The first should come around the midpoint of your study schedule, so you can identify weak areas while you still have time to address them. The second should come in your final week, simulating real test conditions as closely as possible.
After each practice test, don’t just check your score. Go through every question you missed and figure out why you missed it. Did you not know the content? Misread the question? Rush through it? Each type of mistake has a different fix, and this review process is where the most learning happens.
Retake Rules to Keep in Mind
Policies vary by school, but a common rule is that you can take the HESI A2 up to three times in a 12-month period, with a minimum of 60 days between attempts. That waiting period means a failed attempt costs you two months, not just a bad afternoon. It’s worth investing the study time upfront rather than treating the first attempt as a trial run. Check with your specific program for their retake policy, since some schools are stricter than the standard guidelines.
Study Tools Worth Using
Flashcard apps like Quizlet have thousands of pre-made HESI A2 decks covering vocabulary, anatomy terms, and biology concepts. These are useful for daily review sessions of 15 to 20 minutes. For structured content review, a dedicated HESI prep book from a publisher like Mometrix, McGraw-Hill, or Elsevier gives you chapter-by-chapter coverage with practice questions built in.
YouTube is underrated for anatomy and biology review. Short explainer videos on topics like cellular transport or organ systems can clarify concepts that feel abstract on a flashcard. Pair video learning with active recall (close the video, write down what you remember) to lock in the material. Passive watching alone won’t stick.