Association of Schools and Colleges of Optometry (ASCO), administered by the ADA Department of Testing Services
OAT
Optometry Admission Test
The standardized admission exam required by every US optometry school. A multiple-choice battery covering the natural sciences, reading, physics, and quantitative reasoning that gatekeeps entry to a Doctor of Optometry (OD) program.
What's on the exam
ASCO OAT test specifications (four-section format; 2026 Candidate Guide, with updated Organic Chemistry specifications from June 2026)
Survey of the Natural Sciences
100 of 230 items (~43%)Biology (40 items): cell and molecular biology, genetics · Biology: organ systems, physiology, ecology · General chemistry (30 items): stoichiometry, kinetics, equilibrium, thermodynamics · Organic chemistry (30 items): mechanisms, stereochemistry · Acid-base and reaction chemistry
Reading Comprehension
50 of 230 items (~22%)Scientific passage comprehension · Locating explicit detail · Inference and reasoning · Tone and purpose · Evaluating arguments
Physics
40 of 230 items (~17%)Kinematics and Newtonian mechanics · Energy, work, and momentum · Waves, optics, and sound · Electrostatics and circuits · Thermodynamics and fluids
Quantitative Reasoning
40 of 230 items (~17%)Algebra · Numerical calculations and conversions · Quantitative comparison · Probability and statistics · Applied/word problems
Frequently asked questions
How much does the OAT cost?
The OAT costs $520. $520 examination fee (2025-2026) includes administration and score reporting to programs selected at application; partial fee waivers available for qualifying candidates.
How long is the OAT and how many questions does it have?
230 items (Survey of the Natural Sciences 100, Reading Comprehension 50, Physics 40, Quantitative Reasoning 40) — 5 hours 5 minutes total including optional tutorial, break, and survey.
What do you need to pass the OAT?
Scores reported 200-400 in 10-point increments (no pass/fail); competitive scores vary by program.
Can you retake the OAT?
Must wait 60 days between attempts; maximum of four attempts in any 12-month period; three or more total attempts require permission to retest with proof of recent optometry school application; after a fifth attempt, once per 12 months.
What is the best way to study for the OAT?
Start from the official outline and your primary study materials: the exam is weighted by domain (Survey of the Natural Sciences 100 of 230 items (~43%), Reading Comprehension 50 of 230 items (~22%), Physics 40 of 230 items (~17%), Quantitative Reasoning 40 of 230 items (~17%)). Once you've learned the material, spaced-repetition flashcards organized by those domains are an efficient way to retain it and refresh it before test day.
Program in development
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