Advanced
Math Skills Test
Solve for x: 4 * log(x) - log(16) = 0.
Strike out the answers you can rule out, then commit the one you'll defend.
Officer Aptitude Rating · free practice
One browser quiz across the Math Skills Test, the Mechanical Comprehension Test and the Reading Comprehension Test — every item with a worked answer. Read the four choices first, strike what can't be right, then commit the one you'll defend. Independent practice, no sign-up, built to the public OAR outline.
Free practice · 3 OAR subtests
80 items across the three OAR subtests. Filter to a subtest, rule out the distractors, then commit — every answer you lock in unlocks the reasoning behind it. This is independent practice, not the administered ASTB-E and not retired official items.
OAR subtest
Question 1 of 80 0 correct
Advanced
Math Skills Test
Strike out the answers you can rule out, then commit the one you'll defend.
Set complete
The full bank on the app runs hundreds more items across all three OAR subtests, sampled to match the Math / Mechanical / Reading weighting. Restart to run this set again, or step back through the questions you missed.
Exam structure
The Officer Aptitude Rating is the officer-aptitude slice of the ASTB-E, the selection battery used for U.S. Navy, Marine Corps and Coast Guard officer and aviation candidates and administered through NAMI. Its surface area is small and fixed: three subtests, no more. The Math Skills Test covers arithmetic, algebra and geometry. The Mechanical Comprehension Test runs levers, pulleys, gears, fluids and basic physics. The Reading Comprehension Test asks only what a passage supports — never what you already believe.
That small surface is exactly why elimination pays here. Every item is four options with one defensible answer and three distractors engineered to look almost right. Read the four answers before the stem: they show you what the question is really testing and where the trap is set, so you don't re-read and burn time.
This site's own drill weighting across the bank. The administered OAR is adaptive, so the exact item count per sitting varies — confirm the current structure with NAMI.
Scoring
The OAR reports a scaled score — roughly 20 to 80 per the published OAR outline — not a raw count of right answers. There is no single "pass" number to chase, and any site that quotes you one is selling certainty it doesn't have. The mark that matters is the minimum your branch, community and program set, and those differ: an aviation designator, a Surface Warfare path and an OCS package are not held to the same bar, and current NAMI and Navy guidance moves.
So don't aim at a number you read online — aim above the one your recruiter and program confirm for you. On the quiz above, treat every locked answer as a scored commitment: the discipline that keeps a rushed guess from becoming a wrong lock is the same discipline the scaled score rewards.
| The number people chase | Where it's actually set |
|---|---|
| A single "OAR passing score" | No universal mark exists — it's set by branch and program |
| Aviation vs. SWO vs. OCS minimum | Your designator/community and current NAMI guidance |
| The scaled score range | Roughly 20–80 per the published OAR outline |
Test day
The OAR is computer-delivered, and portions are adaptive: the difficulty tracks how you answer, so you generally commit to an item and move on rather than flagging it and circling back the way you would on paper. That single fact rewrites your tactics — you can't harvest the easy questions first, so you have to run the elimination inside each item, before you lock it.
Test-day rules — whether a calculator or scratch paper is provided — are set by current NAMI test-administration guidance and confirmed at your site; prep as if you'll reason arithmetic by hand. Sittings are scheduled on demand through NAMI and authorized locations, so there's no fixed public calendar to plan around.
Round 1 — take what's free
Read the four options, then the stem. If one answer is clearly right and the rest clearly wrong, lock it and move — the adaptive engine won't let you return, so never leave easy points behind.
Round 2 — narrow to two
Can't see it instantly? Strike the two choices that can't hold, then find the single differentiator between the survivors and commit the one you can defend.
Round 3 — commit a reasoned guess
Down to a coin flip, guess and advance — a blank helps no one and you can't revisit it. On the Math Skills Test, estimate first; a ballpark often kills a distractor before you finish the arithmetic.
Retakes
You can retake the OAR, but the number of attempts and the waiting period between sittings are governed by current NAMI policy — and prior attempts count. Treat the exact rule as something to confirm, not memorise from a forum, because it's the kind of figure that changes and gets misquoted.
The tactical takeaway is simpler than the policy: because each sitting is scored and consequential, every item deserves the full narrow-to-two pass. Elimination discipline is what stops a rushed commitment on this attempt from costing you the next one.
Attempts are limited and each one counts — so make every item a two-way call you reasoned into, not a four-way guess you rushed.
Keep drilling
Use the quiz as a diagnostic, not just a score. A missed item is a pointer: the subtest chip it came from is the guide you open next. Miss two mechanical items in a row and it's not bad luck — it's a topic, and the depth guide names it. Then come back and re-run that subtest until the rule-outs are automatic.
Start here
OAR Study Guide
The subtest-by-subtest plan, weighted to where the points are.
Subtest
Math Skills Test
Arithmetic, algebra and geometry — estimate first, then eliminate.
Subtest
Mechanical Comprehension Test
Levers, pulleys, gears and fluids — reason the direction, rule out the rest.
Reading Comprehension Test
Depth guide
Supported-conclusion reading tactics.
Coming soon
Wider battery
ASTB-E Practice Test
Drill beyond the OAR three into the full ASTB-E screen.
FAQ
It's a reasoning test, not a memory test: four choices per item, one defensible answer. The difficulty lives in distractors built to look almost right and in the adaptive format raising the bar as you answer well. Read the options first and rule out the two that can't hold, and most items collapse to a two-way call you can win. Demanding, but bounded — three subtests, nothing exotic.
Right here. The quiz above runs 80 items across all three OAR subtests free, with no sign-up and a worked rationale on every answer. Filter to the Math Skills Test, the Mechanical Comprehension Test or the Reading Comprehension Test to drill a weak area. It's independent practice built to the public OAR outline — not the administered ASTB-E and not retired official items.
Different target. The ASVAB screens enlisted aptitude broadly; the OAR is narrower and officer-facing — three subtests aimed at the reasoning an officer or aviation candidate needs. Many find the OAR's math and mechanical items reason harder per question, but there's less ground to cover. The tactic wins either way: eliminate the impossible answers first.
Treat that as set by current NAMI test-administration guidance, not by anything you read online — what's provided can change and is confirmed at your test site. Prep as if you'll reason arithmetic by hand: on the Math Skills Test, ballpark the answer first, and the estimate alone often rules out two options before you compute.
There's no single pass mark to quote. The OAR is a scaled score — roughly 20 to 80 per the published outline — and the number that counts is the minimum your branch, community and program set. Aviation, Surface Warfare and OCS differ, and current guidance moves. Confirm your target with your recruiter and NAMI, then aim above it, not at it.
Because the OAR is computer-delivered and adaptive, the exact count per sitting isn't fixed the way a paper test is — confirm the current structure with NAMI. What's stable is the shape: three subtests — the Math Skills Test, the Mechanical Comprehension Test and the Reading Comprehension Test — every item four options with one right answer.
OAR Exam Prep
Take the OAR question bank with you
Get the app for the full bank across all three OAR subtests, sampled to the real Math / Mechanical / Reading weighting — or keep drilling free on this site.