NNAAP vs Prometric vs Headmaster vs Credentia vs PHD vs Excel: 2026 CNA Exam Vendor Comparison

Quick reference: all six vendors at a glance

The full at-a-glance table below compares every vendor across the ten attributes candidates care about most. The Headmaster column is highlighted because it covers the most states (24). Scroll horizontally on mobile to see all columns.

★ Highlighted vendor has the highest state coverage. The first column stays visible while you scroll the table horizontally on small screens.

Format comparison: written, skills, and duration

All six vendors use the same two-part format — a multiple-choice written exam plus a 5-skill clinical evaluation — but the specifics vary. Question counts range from 60 (Prometric, Headmaster in two states) to 80 (Excel). Prometric and Headmaster deliver the written portion on computer or tablet; the others offer paper-based testing at some sites. Below is a side-by-side breakdown of the written component, the skills component, and total duration at the testing center.

Key takeaways: Prometric has the shortest written exam (60 questions), making time pressure less acute. Excel has the longest at 80 questions — pace yourself at ~1 minute per question. Headmaster's tablet-based format is the most modern; the others use traditional computer or paper testing. Skills format is essentially identical across vendors: 5 randomly assigned skills, with Hand Hygiene and Indirect Care always included.

Pass rates and difficulty

None of the six vendors publish first-attempt pass rates in a way that makes for a fair cross-vendor comparison. D&S Headmaster self-reports pass rates in the 80-86% range, and Credentia reports 78-86%, but the underlying population of test-takers differs across vendors — some vendors test a larger share of graduates from public training programs, some test more candidates from private programs, and reporting windows vary.

Anecdotally, first-attempt pass rates across all six vendors cluster in the 75-85% range for graduates of state-approved training programs. The biggest variable is preparation, not vendor choice. Candidates who spend 4-6 weeks studying after completing their training program — drilling the critical-step rubric and taking 3-5 full-length timed practice tests — pass at substantially higher rates than those who rely on training-program instruction alone.

On perceived difficulty, candidates occasionally report that computer-based testing (Prometric, Headmaster's tablet) feels more standardized and less anxiety-inducing, while paper-based testing (some NNAAP, Credentia, PHD, and Excel sites) feels more familiar. None of these differences change the underlying difficulty of the questions or the skills evaluation. The most common point of failure across vendors is the clinical skills portion — specifically, candidates who skip the opening hand hygiene step or fail to verify patient identity. These failures are recoverable: most candidates who fail on the first attempt pass on the second try after focused review of the critical-step rubric.

The honest answer is that there is no "easiest" vendor. The exam is challenging by design — every state's nurse aide registry wants to be confident that newly certified CNAs can deliver safe patient care. Pick the vendor your state uses, prepare thoroughly, and you'll pass.

How to prepare regardless of vendor

Because all six vendors test from the same content blueprint and use the same critical-step rubric for the skills portion, preparation strategy is largely universal. Spend 4-6 weeks studying after completing your state-approved training program. Below is the prep plan that works across vendors.

Hand hygiene is the single most-tested skill. Every clinical skills evaluation across every vendor must begin with hand hygiene — the 8-step handwashing sequence with soap and water (or alcohol-based handrub). It's the first thing the evaluator scores, and it's the most-skipped step among first-attempt candidates. Memorize the 8 steps (wet, soap, rub for 20 seconds, rinse, dry, turn off faucet with paper towel) and treat them as automatic, like buckling a seat belt. If you skip this step, you fail the skill regardless of how well you perform the rest.

Practice the critical-step rubric. Every clinical skill has a checklist of steps, some of which are designated "critical." Missing a critical step fails that entire skill, and failing one skill fails the entire skills exam — there is no partial credit. The critical steps typically include verifying patient identity (not just asking their name — check the wristband), providing privacy (closing the door and curtain throughout, not just at the start), and performing hand hygiene. Get your vendor's candidate handbook and review the critical-step checklist for each of the 22-23 skills before exam day.

Take full-length timed practice tests. The written exam is 60-80 questions in 90 minutes depending on vendor — that's anywhere from 67 to 90 seconds per question. Build your timed practice tests to match your vendor's format so you're not surprised on exam day. Review every wrong answer and every question you marked for review; this is where most of the learning happens. Aim for 3-5 full-length timed tests in the final week before your exam.

Drill the content areas. The five content areas cluster around Physical Care (the largest, ~35-40% of questions), Psychosocial Care, Role of the Nurse Aide, Safety, and Infection Control. Spend the most time on Physical Care skills (bed bath, oral care, perineal care, dressing, feeding, ambulation, transfers) and Safety scenarios (RACE protocol for fire, fall prevention, infection control). Memorize the 20-second handwashing standard, the normal vital sign ranges, and the do-not-cut-toenails rule for diabetic residents — these facts show up on every vendor.

Day-of tips: eat a real breakfast, hydrate, arrive 30 minutes before your scheduled time, and bring two forms of government-issued ID. Wear closed-toe non-slip shoes and have your hair tied back. Take a deep breath before the first question — you've prepared, you know the material, and you'll do great.

Frequently asked questions