# OAR Prep

> OAR Prep is a mobile study app for the Navy Officer Aptitude Rating (OAR) test: 2,600+ exam-style practice questions in math, reading and mechanical comprehension, timed mock exams, flashcards and an AI tutor that explains every answer.

OAR Prep is an independent mobile app (iPhone and iPad) for candidates preparing for the U.S. Navy's Officer Aptitude Rating (OAR), the officer aptitude score from the Aviation Selection Test Battery (ASTB-E). It is not affiliated with the U.S. Navy or the Department of Defense.

OAR Prep is part of Exam321.com (https://exam321.com), a family of mobile apps providing a wide variety of exam preps.

## Key facts

- Practice questions: 2,604, grouped into three practice sections, each question with a written explanation
- Mock exams: 90 questions across all three sections, timed
- Flashcards: 89 key math formulas, vocabulary words and mechanical principles
- AI tutor: explains why each answer is right or wrong, with follow-up questions
- Also: daily quiz and streaks, past-errors review quiz, performance by section, test-date countdown, cheatsheet
- Price: free to download; first quiz free; OAR Prep Pro in-app purchase unlocks unlimited access
- Pass Guarantee Program: Premium subscribers who used the app for at least 14 days before the test, did not reach their required score, and email within 14 days of receiving their result get 3 more months of Premium free; repeatable (terms: https://oarprep.com/pass-guarantee; full policy: https://www.znosnie.com/pass-guarantee-policy)
- iPhone and iPad: https://apps.apple.com/us/app/oar-test-practice-prep-2026/id6785844765
- Android: not available yet
- Contact: contact@znosnie.com

## Question bank by practice section

Each section prepares for one OAR subtest (the app calls the reading section "Verbal Skills"):

- Math Skills Test: 1,134 questions — Arithmetic, fractions, percentages, ratios, algebra, geometry and word problems, all without a calculator.
- Reading Comprehension Test: 734 questions — Word knowledge, synonyms, analogies, sentence completion and reading comprehension passages.
- Mechanical Comprehension Test: 736 questions — Levers, pulleys, gears, forces, motion, pressure, energy and simple circuits.

## About the OAR

- Score: Officer Aptitude Rating (OAR), on a 20–80 scale
- Part of: The Aviation Selection Test Battery (ASTB-E); the OAR is three of its subtests
- Subtests: Math Skills, Reading Comprehension and Mechanical Comprehension
- Format: Computer-adaptive multiple choice, at an approved proctored test site; no calculator
- Used for: Navy Officer Candidate School (OCS) and other non-aviation officer programs
- Retakes: 3 lifetime attempts, at least 30 full days apart; your newest score replaces the old one
- Official source: https://www.med.navy.mil/Navy-Medicine-Operational-Training-Command/Naval-Aerospace-Medical-Institute/ASTB-FAQ/

## Pages

- [Home](https://oarprep.com/): app overview, test overview, question bank by section, features, FAQ
- [Blog](https://oarprep.com/blog): OAR study notes and plans
- [Tools](https://oarprep.com/tools): free OAR practice tests, a no-calculator math drill, mechanical comprehension calculators, a formula sheet, a vocabulary list and an ASTB-E retest date calculator
- [Contact](https://oarprep.com/contact): support, question corrections, partnerships
- [Pass Guarantee Program](https://oarprep.com/pass-guarantee): terms for the 3-month Premium extension
- [What Is a Good OAR Score? Ranges and Minimums by Program](https://oarprep.com/blog/what-is-a-good-oar-score): There is no OAR passing score. See the 20–80 scale, what counts as competitive, and the minimum OAR score for SWO, Intel, Supply and other Navy programs.

## Free tools

- [Free OAR practice test](https://oarprep.com/tools/oar-practice-test): Take a free 15-question OAR practice test covering math, reading and mechanical comprehension. Instant scoring and an explanation for every answer.
- [OAR math practice test](https://oarprep.com/tools/oar-math-practice-test): Free OAR Math Skills practice test: 15 word problems, algebra, geometry and probability questions with worked answers. No calculator, like the real test.
- [Mechanical comprehension practice test](https://oarprep.com/tools/oar-mechanical-comprehension-practice-test): Free OAR mechanical comprehension practice test: levers, gears, pulleys, hydraulics, fluids and circuits. 15 questions with answers explained.
- [Reading comprehension practice test](https://oarprep.com/tools/oar-reading-comprehension-practice-test): Free OAR reading comprehension practice test: 15 short passages with main-idea, detail and inference questions, each answer explained.
- [No-calculator math drill](https://oarprep.com/tools/oar-mental-math-drill): Timed no-calculator math drill for the OAR: arithmetic, fractions, percents, exponents and order of operations, with instant feedback.
- [Gear ratio calculator](https://oarprep.com/tools/gear-ratio-calculator): Find the speed, gear ratio, torque change and direction of a driven gear from tooth counts and driver rpm, including idler gears. Worked OAR-style examples.
- [Lever calculator](https://oarprep.com/tools/lever-calculator): Solve any balanced lever problem: effort force, load or arm length from the other three, plus mechanical advantage. With the three lever classes explained.
- [Mechanical advantage calculator](https://oarprep.com/tools/mechanical-advantage-calculator): Calculate mechanical advantage and effort force for pulley systems, inclined planes (ramps) and wheels and axles, the simple machines on the OAR.
- [Hydraulic press calculator](https://oarprep.com/tools/hydraulic-press-calculator): Find a hydraulic press’s output force, pressure, mechanical advantage and piston travel from the input force and piston areas, using Pascal’s principle.
- [Ohm’s law & resistor calculator](https://oarprep.com/tools/ohms-law-calculator): Solve for voltage, current or resistance with Ohm’s law, get power, and add resistors in series and parallel. Simple circuits for the OAR.
- [OAR formula sheet](https://oarprep.com/tools/oar-formula-sheet): The key OAR formulas on one page: arithmetic, algebra, geometry and statistics, plus levers, gears, pulleys, pressure, energy and circuits.
- [OAR vocabulary list](https://oarprep.com/tools/oar-vocabulary-list): A free OAR vocabulary list: 28 words from the OAR Prep verbal flashcards, with definitions, example sentences and a hide-the-meanings self-test.
- [ASTB-E retest date calculator](https://oarprep.com/tools/astb-retest-date-calculator): When can you retake the OAR? Enter your last ASTB-E test date and attempts used to get your earliest retest date and how many attempts you have left.

## Languages

The home and contact pages are available in 2 languages (the blog is English-only):

- [English](https://oarprep.com/) (en)
- [Español](https://oarprep.com/es) (es)

## FAQ

### What is the OAR test?

The Officer Aptitude Rating (OAR) is an aptitude test for people applying to become officers in the U.S. Navy. It is made of three subtests of the Aviation Selection Test Battery (ASTB-E): Math Skills, Reading Comprehension and Mechanical Comprehension. Navy Officer Candidate School and other officer programs use the score to select candidates.

### How is the OAR scored?

The OAR is reported on a scale from 20 to 80. There is no single passing score: each officer program sets its own minimum, and selection boards compare your score with other applicants. Your recruiter can tell you the target for the program you are applying to.

### What is OAR Prep?

OAR Prep is an iPhone and iPad app built only for the OAR. It includes 2,604 exam-style practice questions in math, reading and mechanical comprehension, timed 90-question mock exams, 89 key-term flashcards, a daily quiz and an AI tutor that explains the reasoning behind every answer.

### How long should I study for the OAR?

A common plan is 4 to 8 weeks of steady preparation, longer if math or physics is rusty. You only get three attempts in your lifetime, so it pays to prepare before the first one. OAR Prep is designed around short daily quizzes, a past-errors review, flashcards and a countdown to your test date.

### Is OAR Prep free?

OAR Prep is free to download on the App Store, and your first quiz is free. OAR Prep Pro, an in-app purchase, unlocks unlimited quizzes, practice by section, full-length mock exams, the past-errors review and extended AI tutor access.

### Is OAR Prep affiliated with the U.S. Navy?

No. OAR Prep is an independent study tool and is not affiliated with, sponsored or endorsed by the U.S. Navy, the Department of Defense or the Naval Aerospace Medical Institute. Our questions are original practice questions, not real test items.