Registered Dietitian (RD/RDN) Pass Rate, Format & Study Guide

The Registered Dietitian (RD) credential, also written Registered Dietitian Nutritionist (RDN), is awarded by the Commission on Dietetic Registration (CDR), the credentialing agency of the Academy of Nutrition and Dietetics. The registration examination for dietitians evaluates the ability to perform at entry level as a dietitian: the principles of dietetics, nutrition care for individuals and groups, the management of food and nutrition programs and services, and foodservice systems. It is a computer-adaptive, multiple-choice exam delivered at Pearson VUE test centers.

Registered dietitians provide medical nutrition therapy in hospitals and clinics, lead community and public health nutrition programs, run food and nutrition services, and work in research and industry. The RD/RDN credential is the profession's recognised mark of competence and is the credential many employers and state licensing boards look for, so passing this exam is the gateway to practising as a dietitian in the United States.

The exam is aimed at graduates who have completed a graduate degree and ACEND-accredited coursework and supervised practice, whether through a Didactic Program in Dietetics plus Dietetic Internship, a Coordinated Program, a Graduate Program or a doctorate ISPP, and at internationally trained candidates whose credentials CDR has found eligible. CDR verifies your academic and supervised practice credentials before it authorises you to test.

CDR publishes RD pass statistics by registration pathway. For candidates who passed within one year of their first attempt, the period ending 2025 shows 2,863 of 3,411 passing (83.93%): 85.66% for the Coordinated Program pathway, 83.23% for the Dietetic Internship pathway, 89.79% for the FG Coordinated Graduate pathway and 69.74% for the individualized supervised practice pathway. Most candidates pass, but roughly one in six does not pass within a year.

A candidate who fails, or whose one-year authorisation lapses, must reauthorise with CDR (online at reps.cdrnet.org/reauth or by email) and pay the current examination fee; you may book early, but the appointment itself must fall on or after day 46, a 45-day wait. A candidate who must pass sooner to keep their job may request a one-time 45-day waiver with an employer letter on company letterhead. CDR's handbook says there is currently no limit on the number of attempts; CDR's exam overview page states that a lifetime limit of eight attempts applies to candidates who establish eligibility on or after January 1, 2027. The optional $350 test bundle includes a voucher for a retake at a discounted $100.

The RD exam is computer-adaptive and scored on a scale of 1 to 50, with a minimum passing scaled score of 25. The number of correct answers needed for a 25 varies between exams because each candidate receives a different set of questions: a slightly harder set needs fewer correct answers and a slightly easier set needs more. You answer at least 125 and at most 145 questions, of which 100 to 120 are scored and 25 are unscored pretest items that cannot be told apart from the rest. A candidate who does not reach 125 responses in the three hours of testing time fails as inconclusive. Your printed score report appears when you leave the test center; the content-area scores on it are not used for the pass/fail decision.

The exam is computer-adaptive and of variable length. Each candidate must receive at least 125 questions (100 scored and 25 pretest) and may receive up to 145 (120 scored and 25 pretest); the pretest items cannot be distinguished from scored ones. Every question has four options, each question must be answered before you continue, and you cannot review or change earlier answers. You have three hours of testing time within a 3.5-hour appointment, which also includes a 20-minute tutorial and a 10-minute survey, and an on-screen calculator is provided. Scores run from 1 to 50 and 25 is the minimum passing score.

• Principles of Dietetics21%
• Nutrition Care for Individuals and Groups45%
• Management of Food and Nutrition Programs and Services21%
• Foodservice Systems13%

CDR's 2022–2026 outline, in force for exams taken through December 31, 2026, has four domains: Principles of Dietetics (21%), Nutrition Care for Individuals and Groups (45%), Management of Food and Nutrition Programs and Services (21%) and Foodservice Systems (13%). From January 1, 2027 CDR's 2027–2031 outline applies instead: Fundamentals of Dietetics Practice (23%), covering management and leadership, marketing and public relations, research applications and professional practice; Community and Public Health Nutrition (22%); Human Nutrition and Medical Nutrition Therapy (40%), covering the nutrition care process from screening to monitoring and evaluation; and Food Science and Food Systems (15%).

CDR requires a minimum of a graduate degree from a USDE-recognised accredited institution (or an equivalent foreign degree), coursework from an ACEND-accredited program (a DPD, Coordinated Program or Graduate Program) and supervised practice from an ACEND-accredited program (a Dietetic Internship, Coordinated Program, Graduate Program or doctorate ISPP). Foreign-degree candidates need a transcript evaluation and a program director's review, and CDR lists separate routes for Canadian, Dutch, Philippine and Irish registered dietitians. Candidates must also agree to CDR's Code of Ethics and a non-disclosure agreement. Authorisation to test lasts one year and expires when you take the exam, if the year ends, or if you miss the cancellation window or arrive late.

CDR's handbook lists the examination fee for dietitians as $250, which is separate from Academy membership dues and CDR registration maintenance fees and is paid by credit card at booking. The optional test bundle costs $350 in total, for the first attempt plus a discount retake voucher (the voucher is priced at $100 and must be bought at checkout with a full-price exam; it is non-refundable and non-transferable). Refunds are given only for online cancellations made at least 48 hours before the appointment, not for failed attempts or no-shows.

To keep the registration you pay a registration maintenance fee by August 31 each year (CDR lets you prepay five years at the start of a cycle) and complete the Professional Development Portfolio once every five years: a learning plan, an activity log of 75 CPEUs for RDs including at least 1 CPEU in ethics or health equity, and a self-assessment. Recertification cycles end on May 31.

CDR's current outline (valid for exams taken through December 31, 2026) weights Nutrition Care for Individuals and Groups at 45%, Principles of Dietetics at 21%, Management of Food and Nutrition Programs and Services at 21% and Foodservice Systems at 13%, so medical nutrition therapy and the nutrition care process deserve the largest share of your time. Because the exam is adaptive and you cannot go back, practise answering decisively: work through domain-by-domain questions first, then timed sets that mimic a 125–145 question sitting in three hours. If your test date falls on or after January 1, 2027, check CDR's 2027–2031 outline first, which reweights the domains to 23% / 22% / 40% / 15%.

CDR reviews the exam content outline every five years. The 2022–2026 outline ends on December 31, 2026 and the 2027–2031 outline (approved June 25, 2025) takes effect January 1, 2027. CDR's exam overview page also states a lifetime limit of eight attempts for candidates who establish eligibility on or after January 1, 2027. Confirm the outline and policies that apply to your test date on CDR's website before you book.