Nursing TEAS vs HESI A2: Which Exam is Harder?

The Pre-Nursing Gauntlet

You are applying to five different BSN programs. Three of the programs require you to submit an ATI TEAS score. Two of the programs require you to submit an Elsevier HESI A2 score.

You have to study for both. Panic sets in as you wonder: Which test is harder? Should I focus all my energy on the TEAS schools or the HESI schools?

The Structural Differences

Both exams are designed to predict if you will survive the first semester of nursing school. However, they attack your brain in completely different ways.

The ATI TEAS (Test of Essential Academic Skills)

Format: Rigid. You must take all four sections (Reading, Math, Science, English). You cannot skip sections.

Science Focus: The TEAS science section is notoriously brutal. It focuses heavily on deep, systemic Human Anatomy and Physiology, alongside chemistry and biology.

Difficulty: Generally considered by students to be the harder of the two exams because of the intense, unforgiving science questions.

The HESI A2 (Health Education Systems, Inc.) Format: Modular. The HESI has 9 different potential sections (including Physics and Chemistry). However, the nursing school gets to choose which sections you take.* A school might only require you to take Math, Reading, and Anatomy.

Science Focus: More generalized. While Anatomy is heavily tested, the questions are often considered more surface-level than the TEAS.

Difficulty: Generally considered slightly easier, largely because you can focus your studying on the specific modules your target school requires, rather than studying for a massive, comprehensive exam.

The Math Reality

While students debate the science sections, the real killer on both exams is the Math section.

Neither test allows you to bring your own calculator (a basic on-screen calculator is provided). Both tests heavily emphasize fractions, decimals, ratios, and metric conversions. Why? Because if a nurse cannot instantly convert milligrams to micrograms, they will kill a patient through a medication error.

If you are weak in basic algebra and fraction manipulation, both the TEAS and the HESI will destroy your application. Master medical math first.