RDN Study Guide 2026

Everything you need to pass the RDN exam in one place: the exam format, every topic to study, real practice questions with explanations, flashcards, and full-length practice tests. Free, no sign-up needed.

RDN exam key facts

The RD exam is computer-based and variable length, with 125 to 145 questions including 25 unscored pretest questions. Source
RD exam candidates have three hours to complete the exam within a 3.5-hour appointment. Source
The RD exam fee is $250 per attempt, paid by credit card when the exam appointment is registered. Source
RD exam candidates may retest after 45 calendar days, with the appointment on or after day 46, and must reauthorize first. Source
Candidates approved for RD registration eligibility are authorized to test for one year at a time. Source

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📋 RDN Exam Format at a Glance

125

Questions

180 min

Time Limit

70.00%

Passing Score

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📚 RDN Topics to Study (29)

Dietary Assessment · 7 cards Dietary Assessment · 7 cards Dietary Assessment · 7 cards Dietary Assessment · 7 cards Food Safety · 7 cards Food Safety · 7 cards Medical Nutrition Therapy · 7 cards Medical Nutrition Therapy · 7 cards Medical Nutrition Therapy · 7 cards Medical Nutrition Therapy · 7 cards Professional Skills · 7 cards Professional Skills · 7 cards Professional Skills · 7 cards Professional Skills · 7 cards Research and Evidence-Based Practice · 7 cards Research and Evidence-Based Practice · 7 cards Research and Evidence-Based Practice · 7 cards Clinical Nutrition · 6 cards Community Nutrition · 6 cards Dietary Assessment · 6 cards Food Safety · 6 cards Food Service Management · 6 cards Lifecycle Nutrition · 6 cards Medical Nutrition Therapy · 6 cards Nutritional Biochemistry · 6 cards Career Pathways · 5 cards Education and Credentialing · 5 cards Professional Skills · 5 cards Scope of Practice · 5 cards

✍️ Sample RDN Questions & Answers

1. A prospective cohort study design in nutritional epidemiology is characterized by:

✓ Following disease-free individuals forward in time and observing who develops disease based on dietary patterns

Prospective cohort studies enroll disease-free individuals, collect baseline dietary data, and follow them forward over time to observe incident disease, allowing assessment of temporal exposure-outcome relationships.

2. Which study approach is most effective for Nutritional Biochemistry material?

✓ Active recall with practice questions

Active recall through practice questions is the most effective study method, as it strengthens memory retrieval pathways.

3. A premature infant born at 28 weeks gestation requires parenteral nutrition. The appropriate initial protein provision should be:

✓ 3.5–4.0 g/kg/day

Extremely premature infants require aggressive early protein provision of 3.5–4.0 g/kg/day via PN to replicate intrauterine accretion rates and support brain development.

4. A hospital RDN is asked to develop a policy for nutrition screening of all inpatients. Which resource would be MOST appropriate to consult first?

✓ The Joint Commission standards and current evidence-based clinical practice guidelines

Policy development should be guided by accreditation standards such as those from The Joint Commission along with current evidence-based clinical guidelines.

5. What is the relationship between theory and practice in Lifecycle Nutrition?

✓ Theory provides the foundation; practice applies it to real situations

Theory provides the conceptual foundation and principles, while practice involves applying those concepts to real-world situations. Both are essential for competence.

6. An Institutional Review Board (IRB) in research is PRIMARILY responsible for:

✓ Protecting the rights, safety, and welfare of human research participants

IRBs review research protocols involving human subjects to ensure ethical standards are met, focusing on protecting participant rights, safety, and welfare before and during a study.

🎯 Free RDN Practice Tests

Professional Skills · 7 questions Research and Evidence-Based Practice · 7 questions Research and Evidence-Based Practice · 7 questions Research and Evidence-Based Practice · 7 questions Food Safety · 7 questions Food Safety · 7 questions Dietary Assessment · 7 questions Dietary Assessment · 7 questions Dietary Assessment · 7 questions Medical Nutrition Therapy · 7 questions

📖 RDN Guides & Articles

Your RDN Study Path

1. Learn with Flashcards → 2. Drill Practice Tests → 3. Take the Full Exam Simulation

🃏 RDN Flashcards (187)🏆 RDN Exam Simulation

What Practice Test Geeks adds beyond an AI chat for RDN

An AI chatbot can quiz you, but it can't reproduce the exam conditions or keep your record. Here you get:

A timed, full-length RDN mock exam — 125 questions in 180 minutes with a 70% pass mark, modeled on the official exam's question count and time limit, followed by a score report broken down by exam domain.
A fixed RDN question bank: the same test every attempt, so your score is comparable from one try to the next instead of changing with every regenerated quiz.
Progress saved on your device: completed tests, scores and missed questions stay in My Progress, so you can retake only what you got wrong.
A printable RDN cheat sheet you can print or save as a PDF.
RDN flashcards built from the same question bank.
Free RDN practice tests with the correct answer shown after each question.

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How this page was made: written with AI tools and published by Nathan Beja, founder of Practice Test Geeks, who is responsible for its content. Exam facts are checked against the official sources listed below. Not reviewed by a subject-matter expert. Editorial policy

Sources & references

Exam facts on this page (fees, format, dates, passing scores) are checked against these official sources; the date is our last check. Editorial policy

admin.cdrnet.org — Exam information · verified Nov 2026
cdrnet.org — Eligibility, fees, exam format, retake fee, time limit, score validity, retake policy, score release, test delivery, test dates · verified Oct 2026