CDR Registration Examination for Dietitians (RD/RDN Exam)
The credentialing exam for registered dietitian nutritionists — medical nutrition therapy, community nutrition, management and food systems on CDR's 2027 test specifications.
About the exam
The Registration Examination for Dietitians is the national credentialing exam you pass to become a Registered Dietitian (RD) or Registered Dietitian Nutritionist (RDN). It is administered by the Commission on Dietetic Registration, the credentialing agency of the Academy of Nutrition and Dietetics. Since January 1, 2024 a minimum of a graduate degree is required to become eligible, along with an accredited didactic program and supervised practice.
The exam is computer adaptive: you answer between 125 and 145 four-option multiple-choice questions (100–120 scored plus 25 unscored pretest items) in up to 3 hours. You can't skip, review or change answers. Scores are reported on a scale of 1 to 50 and you need 25 to pass; you get your score report when you leave the test center.
Our practice follows CDR's 2027–2031 test specifications — medical nutrition therapy, the Nutrition Care Process and PES statements, enteral and parenteral nutrition calculations, community and public health nutrition, management and finance, and food science and food systems — with every calculation explained step by step, plus flashcards, worked cases, illustrated guides and full-length timed practice.
How we track your progress
Every blueprint domain moves through five levels as you study:
- Not startedNo questions answered in this domain yet.
- Getting startedFirst questions answered — not enough yet to judge.
- DevelopingAt least 5 answered and 50% or better on your recent questions.
- ProficientAt least 15 answered and 70% or better on your recent questions.
- Exam readyAt least 25 answered, 80% or better recently, and holding up on hard questions.
The exam blueprint
CDR RD Test Specifications 2027–2031 (approved June 25, 2025; effective January 1, 2027). Candidates testing through December 31, 2026 are tested on the 2022–2026 specifications, which cover largely the same content under different domain names. — Fundamentals of Dietetics Practice 23% · Community and Public Health Nutrition 22% · Human Nutrition and Medical Nutrition Therapy 40% · Food Science and Food Systems 15%. Tap a domain to see its topics.
1 Fundamentals of Dietetics Practice 23% of scored items of the exam
104 practice questions in this domain so far
2 Community and Public Health Nutrition 22% of scored items of the exam
99 practice questions in this domain so far
3 Human Nutrition and Medical Nutrition Therapy 40% of scored items of the exam
180 practice questions in this domain so far
4 Food Science and Food Systems 15% of scored items of the exam
67 practice questions in this domain so far
What you get when you access this exam
Free with your QuizMe account.
Built on CDR's 2027 test specifications
Every question is tagged to an RD domain and topic — MNT, the Nutrition Care Process, community nutrition, management and food systems.
Hints that teach
Reveal the formula, guideline or PES logic behind a question when you're stuck. Every answer explains why the right choice is right and why the others aren't.
Every calculation worked out
Energy and protein needs, tube-feeding and PN formulas, food cost, yield and FTEs — each solved step by step so you can repeat it on exam day.
Timed practice tests
125 questions in 3 hours, with a pacing indicator, full review and an estimated scaled score.
Flashcards, cases and guides
Flashcards for formulas and standards, worked patient and management cases, and interactive illustrated guides.
Progress in every domain
Each domain moves from Not started to Exam ready, so you know exactly what to study next.
Test at home or at a center
After your program director submits your eligibility, CDR authorizes you to test — usually in under a week — and you schedule with Pearson VUE. Your authorization is good for one year.
At a Pearson VUE test center
- More than 250 approved Pearson VUE centers; testing is by appointment, year-round.
- Bring current government-issued photo ID that matches your authorization name.
- A basic on-screen calculator is available for calculation items.
- Your score report — scaled score and sub-scores — prints as you leave.
Before you schedule
- Know which specifications apply: tests through Dec 31, 2026 use the 2022–2026 spec; from Jan 1, 2027 the 2027–2031 spec applies.
- You can't skip, review or change answers — practice committing to your best choice.
- Stopping before the minimum number of questions means the exam isn't scored and no refund is given.
- If you need to retest, wait 45 days and request reauthorization from CDR.
Exam-day game plan
How to walk in ready — and how to pace 125 questions in 3 hours.
Pacing checkpoints
Our timed test gives you the minimum real length — 125 questions — in the full 3 hours. The real exam is adaptive and may continue up to 145 questions, 25 of them unscored pretest items you can't identify.
The week before
- Take one full timed practice test 4–5 days out, then rest.
- Drill your formulas: Mifflin-St Jeor, protein and fluid needs, tube-feeding and PN calories, food cost percent and FTEs.
- Review PES statement structure and the four steps of the Nutrition Care Process.
- Confirm your Pearson VUE appointment and ID.
During the test
- Read the last line of the question first — then the scenario.
- Pick the answer for the RDN's scope and the next best step, not every true statement.
- Write formulas on your noteboard before calculating, and check units.
- There's no going back — make your best choice and move on.
Keep your head
- Adaptive tests feel hard for everyone — difficulty adjusts to keep challenging you.
- If you stop at 125 questions you may well have passed; if it continues, keep going steadily.
- A few tough questions in a row tell you nothing about your score.
After you pass
- You earn the RD (or RDN) credential and join the CDR registry.
- Recertify every 5 years with 75 continuing professional education units (CPEUs), at least 1 in ethics or health equity.
- Plan your CPEUs with the Professional Development Portfolio: Learning Plan, Activity Log, then Self-Assessment.
- Pay the annual registration maintenance fee by August 31 each year (or all five years at once).
Official sources and further reading
- CDR — RD Test Specifications 2027–2031 (PDF) ↗Official domains, weights and expanded study outline from Jan 1, 2027.
- CDR — Exam FAQ 2025 (PDF) ↗Exam length, timing, scoring, fee and retake rules.
- CDR — Recertification information ↗75 CPEUs, the 5-year cycle and the Professional Development Portfolio.
Ready to start?
450 questions and scenarios across the blueprint — and growing.
RD®, RDN® and the Registration Examination for Dietitians are owned by the Commission on Dietetic Registration (CDR). QuizMe and thinQtank Learning are not affiliated with or endorsed by CDR or the Academy of Nutrition and Dietetics. All questions are original. Details are summarized from CDR's official pages; fees and policies change — always confirm at cdrnet.org. Estimated scores are rough guides, not official conversions.