ASVAB study guide: what to study first

1. The AFQT four. Arithmetic Reasoning, Math Knowledge, Word Knowledge and Paragraph Comprehension make the score that decides eligibility. If you are near your branch's floor (scores by branch), spend most of your time here.
2. The subtests behind your job. Look up the line score your target job uses on jobs by score and the subtests in it on line scores. A mechanic's job sends you to Mechanical Comprehension and Auto and Shop; an electronics job to Electronics Information and General Science.
3. A mixed run under time. Finish with the practice test, which jumps between subjects as the real session does.

If you have no job in mind yet, Mechanical Comprehension (in 7 of the 14 Army, Air Force and AFQT composites) and Auto and Shop (6) feed the most composites outside the AFQT four; Assembling Objects feeds no Army or Air Force composite.

Arithmetic Reasoning gets far more time per question than Word Knowledge, which runs at well under a minute per word. Practice the fast subtests against a timer and the slow ones for accuracy.

• Week 1: a mixed practice set to see which areas lag, then daily arithmetic word problems.
• Week 2: algebra and geometry rules, plus 20 vocabulary words a day learned with their prefixes and roots.
• Week 3: reading passages and the line-score subtests for your target job.
• Week 4: timed mixed sets, review of every missed question, and rest before the test.

Shorten or stretch it to your test date; keeping the order counts for more than the number of weeks.

• Arithmetic Reasoning: taking a percent of the wrong base and averaging speeds that should be weighted by time.
• Math Knowledge: sign errors with negative numbers and confusing area with perimeter.
• Word Knowledge: choosing a word that is related to the target but does not mean the same.
• Paragraph Comprehension: answering from what you know instead of from the passage.
• General Science: mass versus weight and speed versus velocity.
• Electronics Information: mixing up series and parallel resistance.
• Auto and Shop: the stroke order of an engine and the purpose of similar-looking tools.
• Mechanical Comprehension: expecting a machine to save work instead of trading force for distance.

Each subtest page lists more traps next to its own question set.

It tends to feel hard by design. On the computer version each question is picked by how you answered the last ones, so almost everyone meets questions near the edge of what they can do, and a strong student can walk out feeling unsure. The result is a percentile, not a grade, so that feeling says little about your score.

What makes it difficult in practice is breadth and speed: nine areas in one sitting, no calculator, and a few subtests that leave well under a minute per item.

officialasvab.com, the test owner's site, has sample questions and the test information for applicants; it does not endorse any prep method. Commercial books such as Wiley's ASVAB For Dummies and courses from test-prep companies cover the same subtests in more depth. Before buying, make sure the edition describes the computer version and no calculator. High school math, English and science courses help with the AFQT subtests, and shop or electronics classes with the technical ones, as officialasvab.com itself suggests.