What should I study for the ASVAB?

Start with the four subtests that make the AFQT, the score that decides enlistment: Arithmetic Reasoning, Mathematics Knowledge, Word Knowledge and Paragraph Comprehension. The testing program says "AFQT scores are computed using the Standard Scores from four ASVAB subtests," and its technical bulletin prints the formula AFQT = AR + MK + 2(VE), where VE is the verbal composite of Word Knowledge and Paragraph Comprehension.

What subjects are on the ASVAB?

Ten subtests in four domains (Verbal, Math, Science and Technical, and Spatial): General Science, Arithmetic Reasoning, Word Knowledge, Paragraph Comprehension, Mathematics Knowledge, Electronics Information, Auto Information, Shop Information, Mechanical Comprehension and Assembling Objects.

How long is the ASVAB?

On the computer test the ten subtests have 135 scored questions and 197 minutes of testing time in total, by the testing program's table: from 6 minutes for Shop Information to 55 minutes for Arithmetic Reasoning. Tryout questions that do not count can add to both.

Should I guess on the ASVAB?

It depends on the version. On the computer test the program says to "try to read and legitimately answer the questions, rather than filling in random guesses for the remaining items, as the CAT-ASVAB applies a relatively large penalty when several incorrect answers are provided toward the end of a subtest." On the paper test: "Answer every question... there is no penalty for guessing."

Can I go back and change an answer on the ASVAB?

Not on the computer test: "you aren’t allowed to return to a question once you have answered it." On the paper test you can review your answers inside a subtest, but not go back to an earlier subtest.

What math is on the ASVAB?

Two subtests. Arithmetic Reasoning is word problems: "operations with whole numbers, operations with rational numbers, ratio and proportion, interest and percentage, and measurement." Mathematics Knowledge "involve[s] number theory, numeration, algebraic operations and equations, geometry and measurement, and probability." No calculator is allowed on either.

ASVAB Study Guide: What Each of the 10 Subtests Covers

Q: Does the ASVAB program recommend a study guide?

No commercial one. Its own words: "The ASVAB Testing Program does not endorse any particular method of test preparation beyond recommending that examinees take a solid core of courses in mathematics, English, and science in high school and/or college." It names free practice at asvabprogram.com/student, officialasvab.com and the Army's march2success.com.

The ten subtests at a glance

In the order the test gives them. Questions and minutes are the computer test's, without tryout questions.

ASVAB subtests: questions, time limit and whether each counts toward the AFQT
Subtest	Questions	Minutes	Counts toward AFQT
General Science (GS)	15	12	No: job qualification only
Arithmetic Reasoning (AR)	15	55	Yes
Word Knowledge (WK)	15	9	Yes, twice (in VE)
Paragraph Comprehension (PC)	10	27	Yes, twice (in VE)
Mathematics Knowledge (MK)	15	31	Yes
Electronics Information (EI)	15	10	No: job qualification only
Auto Information (AI)	10	7	No: job qualification only
Shop Information (SI)	10	6	No: job qualification only
Mechanical Comprehension (MC)	15	22	No: job qualification only
Assembling Objects (AO)	15	18	No: job qualification only

Which subtests decide whether you can enlist

The testing program: "AFQT scores are computed using the Standard Scores from four ASVAB subtests: Arithmetic Reasoning (AR), Mathematics Knowledge (MK), Paragraph Comprehension (PC), and Word Knowledge (WK)." Its technical bulletin gives the weights: "A verbal composite (VE) score is formed from an optimally weighted composite of unrounded WK and PC standard scores (Segall, 2004). VE, in turn, is double-weighted in the computation of AFQT scores", and prints the formula as AFQT = AR + MK + 2(VE).

So Word Knowledge and Paragraph Comprehension together carry the same weight as the two math subtests combined. The other six subtests do not change the AFQT. They matter after it: "Scores on the AFQT are used to determine your eligibility for enlistment in the Army, Navy, Air Force, or Marine Corps. Scores on all of the ASVAB tests are used to determine the best job for you in the military." The ASVAB jobs pages show which subtests each service's job scores use.

General Science (GS)

15 questions in 12 minutes on the computer test · paper test: 25 in 11 minutes · Science/Technical domain

What it measures: "Knowledge of physical and biological sciences"

What it covers: "General Science tests the ability to answer questions on a variety of science topics drawn from courses taught in most high schools. The life science items cover botany, zoology, anatomy and physiology, and ecology. The earth and space science items are based on astronomy, geology, meteorology, and oceanography. The physical science items measure force and motion mechanics, energy, fluids, atomic structure, and chemistry."

Practice General Science: 15 questions with every answer explained

Arithmetic Reasoning (AR)

15 questions in 55 minutes on the computer test · paper test: 30 in 36 minutes · Math domain · counts toward the AFQT

What it measures: "Ability to solve arithmetic word problems"

What it covers: "Arithmetic Reasoning tests the ability to solve basic arithmetic problems one encounters in everyday life. One-step and multi-step word problems require addition, subtraction, multiplication, and division, and choosing the correct order of operations when more than one step is necessary. The items include operations with whole numbers, operations with rational numbers, ratio and proportion, interest and percentage, and measurement. Arithmetic reasoning is one factor that helps characterize mathematics comprehension and logical thinking."

Practice Arithmetic Reasoning: 15 questions with every answer explained

Word Knowledge (WK)

15 questions in 9 minutes on the computer test · paper test: 35 in 11 minutes · Verbal domain · counts toward the AFQT

What it measures: "Ability to select the correct meaning of words presented in context and to identify the best synonym for a given word"

What it covers: "Word Knowledge tests the ability to understand the meaning of words through synonyms—words having the same or nearly the same meaning as other words. The test is a measure of one component of reading comprehension since vocabulary is one of many factors that characterize reading comprehension."

Practice Word Knowledge: 15 questions with every answer explained

Paragraph Comprehension (PC)

10 questions in 27 minutes on the computer test · paper test: 15 in 13 minutes · Verbal domain · counts toward the AFQT

What it measures: "Ability to obtain information from written passages"

What it covers: "Paragraph Comprehension tests the ability to obtain information from written material. Students read different types of passages of varying lengths and respond to questions based on information presented in each passage. Concepts include identifying stated and reworded facts, determining a sequence of events, drawing conclusions, identifying main ideas, determining the author’s purpose and tone, and identifying style and technique."

Practice Paragraph Comprehension: 10 questions with every answer explained

Mathematics Knowledge (MK)

15 questions in 31 minutes on the computer test · paper test: 25 in 24 minutes · Math domain · counts toward the AFQT

What it measures: "Knowledge of high school mathematics principles"

What it covers: "Mathematics Knowledge tests the ability to solve problems by applying knowledge of mathematical concepts and applications. The problems focus on concepts and algorithms and involve number theory, numeration, algebraic operations and equations, geometry and measurement, and probability. Mathematics knowledge is one factor that characterizes mathematics comprehension and assesses logical thinking."

Practice Mathematics Knowledge: 15 questions with every answer explained

Electronics Information (EI)

15 questions in 10 minutes on the computer test · paper test: 20 in 9 minutes · Science/Technical domain

What it measures: "Knowledge of electricity and electronics"

What it covers: "Electronics Information tests understanding of electrical current, circuits, devices, and systems. Electronics information topics include electrical circuits, electrical and electronic systems, electrical currents, electrical tools, symbols, devices, and materials."

Practice Electronics Information: 15 questions with every answer explained

Auto Information (AI)

10 questions in 7 minutes on the computer test · paper test: With Shop: 25 in 11 minutes · Science/Technical domain

What it measures: "Knowledge of automobile technology"

What it covers: "Auto and Shop Information tests aptitude for automotive maintenance and repair, and wood and metal shop practices. The test covers several areas commonly included in most high school auto and shop courses such as automotive components, automotive systems, automotive tools, troubleshooting and repair, shop tools, building materials, and building and construction procedures."

Practice Auto Information: 10 questions with every answer explained

Shop Information (SI)

10 questions in 6 minutes on the computer test · paper test: With Auto: 25 in 11 minutes · Science/Technical domain

What it measures: "Knowledge of tools and shop terminology and practices"

Practice Shop Information: 10 questions with every answer explained

Mechanical Comprehension (MC)

15 questions in 22 minutes on the computer test · paper test: 25 in 19 minutes · Science/Technical domain

What it measures: "Knowledge of mechanical and physical principles"

What it covers: "Mechanical Comprehension tests understanding of the principles of mechanical devices, structural support, and properties of materials. Mechanical comprehension topics include simple machines, compound machines, mechanical motion, and fluid dynamics."

Practice Mechanical Comprehension: 15 questions with every answer explained

Assembling Objects (AO)

15 questions in 18 minutes on the computer test · paper test: 25 in 15 minutes · Spatial domain

What it measures: "Ability to determine how an object will look when its parts are put together"

What it covers: ASVAB Technical Bulletin No. 3 describes two kinds of item, given in a fixed order on the computer test: "Administration of the AO test is content-balanced among the Puzzle (P) and Connection (C) content areas using the following administration sequence: CCCCCCCPPPPPPPP." Seven connection items come first, then eight puzzles.

Practice Assembling Objects: 15 questions with every answer explained

What the testing program says about preparing

"The ASVAB Testing Program does not endorse any particular method of test preparation beyond recommending that examinees take a solid core of courses in mathematics, English, and science in high school and/or college."

Its page on test preparation lists what it recommends, and nothing else: "The only recommended preparation for the ASVAB is"

"taking a solid core of high school and/or college courses in mathematics, English, and science;"
"reviewing free ASVAB practice tests or sample questions found at https://asvabprogram.com/student and https://www.officialasvab.com/applicants/sample-questions; and"
"using the Army’s free online courses and test-prep programs found at https://www.march2success.com."

The free official practice it names

Official sample questions: The testing program's own samples for each of the 10 subtests. Free, no login.
ASVAB Career Exploration Program, student page: Sample questions for the paper test and the school computer test, from the Department of Defense program that gives the same battery in schools.
March2Success: Free online courses sponsored by the U.S. Army: "there is absolutely no obligation on your part to connect with the Army." Registration is required.

Rules that change how you answer

On the computer test you cannot go back: "Be sure the answer you have selected is the one you want to select, as you aren’t allowed to return to a question once you have answered it."
On the computer test, do not fill in random guesses at the end: "If time is running short, try to read and legitimately answer the questions, rather than filling in random guesses for the remaining items, as the CAT-ASVAB applies a relatively large penalty when several incorrect answers are provided toward the end of a subtest."
On the paper test, answer every question: "Answer every question. If you run out of time, it is to your advantage to fill in random guesses for the remaining items, as there is no penalty for guessing."
On both versions, rule choices out first: "When you don’t know the answer to a question, try to rule out as many incorrect choices as you can, and then make an educated guess from the remaining answers."
No calculator: "You cannot use a calculator when taking the ASVAB."

ASVAB Study Guide