A Guide to the OAT for International Students

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By Shorelight Team
Last updated on October 24, 2023

If you want to become an optometrist, first ask yourself, what do you know about the Optometry Admissions Test (OAT)? Scoring high on the OAT is key to getting into one of the US’s 23 optometry programs.

An international student optometrist in training looks through an optometry lens at an optometry patient

Becoming an optometrist, or eye doctor, requires earning a Doctor of Optometry (OD) from a school of optometry. Getting accepted to one of the 23 optometry programs in the United States requires taking the Optometry Admissions Test, or OAT. 

What Is the OAT?

The OAT is a standardized exam administered by the American Dental Association (ADA) on behalf of the Association of Schools and Colleges of Optometry (ASCO). What does the OAT measure? This standardized test evaluates a test taker’s conceptual understanding and analytical skills necessary to practice optometry. 

Here is everything prospective optometry students need to know about this competitive grad school test. We will go over questions including how long does the OAT take, how the OAT score is calculated, and what is considered a good OAT score.


October 2023 update

With the easing of COVID-19 restrictions, Prometric, the global testing services provider, has resumed testing in more than 98% of their global test centers at either full or limited occupancy. Reopened test centers will not require masks to be worn in test centers, but will encourage students to follow health measures regardless of mandate or vaccination status. 

If your appointment for the OAT exam is affected due to continued site closures or regional restrictions, Prometric will notify you and guide you through the next steps: you can choose to cancel or reschedule. You will receive a full refund if your exam payment was processed through Prometric. Your appointment will be rescheduled to a new date depending on when testing will resume.

The fee to reschedule an exam depends on the testing organization, as does the amount of time you have to reschedule without a penalty. Any cancellations or reschedulings will require a fee payable directly to Prometric. Make sure to arrive on time, because if you miss a scheduled exam or arrive 30 minutes after the start time, you may not be able to sit for the exam and will forfeit the full testing fee. Keep in mind that Prometric only accepts valid government-issued IDs, unless specified by the test sponsor.

If you are unable to travel to an official testing center because of illness or travel restrictions, do not worry: you can email your concerns to testingproblems@ada.org and request to reschedule or cancel your appointment.

For more specifics, please visit the Prometric COVID-19 FAQ website or the OAT exam website.

If you have any questions or need assistance, please reach out to a Shorelight representative.


What Is the Structure of the OAT? 

More specifically, how many sections does the OAT exam have? How many questions are on OAT? 

The OAT is a computer-administered, multiple-choice test with four sections:

  1. Survey of the Natural Sciences: This 90-minute section includes 100 questions in three subsections: Biology (40 questions), General Chemistry (30 questions), and Organic Chemistry (30 questions). An on-screen periodic table is provided.

  2. Reading Comprehension: Test takers will have 60 minutes to complete 50 questions. There are three passages to read, then questions to answer that test comprehension and the ability to analyze scientific content.

  3. Physics: This 50-minute section has 40 questions. Tested topics include units and vectors, linear kinematics, statics, dynamics, rotational motion, energy and momentum, simple harmonic motion, waves, fluid statics, thermal energy and thermodynamics, and more.

  4. Quantitative Reasoning: OAT’s final section takes 45 minutes to cover 40 questions. Examinees will work on algebra, data analysis, interpretation and sufficiency, quantitative comparison, probability and statistics, and mathematical word problems. In the OAT, both the US customary system and the metric system (Imperial System) of units are used. An on-screen calculator is provided, as well as two noteboards and markers. No personal calculators, writing utensils, or paper are allowed in the testing room.

You can get a more detailed breakdown of covered topics by reading the ADA’s OAT Candidate Guide.


There is no penalty for guessing, so that means you should answer every question before time runs out on the section. 

How Long Is the OAT? How Long Does It Take to Get OAT Scores?

The OAT takes five hours and five minutes to complete, including an optional 15-minute tutorial, a 30-minute break, and a 15-minute optional survey after the test. After the test is finished, you will receive an unofficial score report at the test center. Be sure to take your test four weeks before your application deadlines to ensure on-time reporting. 

How Is the OAT Scored? What Is a Good OAT Score?

Raw scores for each section are converted to a scale between 200 and 400 in increments of 10 points. Scores range from 200 to 400, with a median score of 300, and a good score is 350.

When Is OAT Registration? When Are OAT Test Dates 2023?

The exam is offered year-round at Prometric centers. You must apply to take this exam 60 to 90 days before you wish to take the test. A PIN from ASCO is required for registration. 

How Much Does It Cost to Take the OAT?

Exam fees for OAT are $515. A limited number of partial fee waivers are available if the exam fee is not affordable to you. The waiver covers 50% of the OAT fee. Cancellation or rescheduling fees are applied based on the amount of time until the test date. 

OAT testing fees will change effective  July 1, 2023, through June 30, 2024. Students who plan to take the OAT after June 2024 are recommended to review the fee rate updates on the OAT website.

How Many Times Can OAT Be Taken?

The OAT can be taken an unlimited number of times, with 60 days between tests. After three attempts, you must apply for permission for retesting. Only a maximum of four attempts are permitted during any 12-month period. Scores cannot be voided after the exam has begun. All scores will be reported to the test taker’s designated colleges or universities.


The OAT is less complex and lengthy than the MCAT. If you have taken the MCAT, a lot of the same biology and chemistry prep will be applicable, but be sure to review OAT-specific physics and math materials. 

How to Study for OAT

Depending on how much time you can dedicate per week to studying, plan on two to three months of preparation for the OAT. ADA sells official study materials including practice exams, and offers a list of reference texts for review. Commercial test prep alternatives that include OAT math practice tests are available from Kaplan and OATBooster.

Make sure you are ready for OAT test day with this simple checklist. Good luck on your first step toward your dream career in optometry!

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