ASVAB study guide: prepare by subtest, aim at a line score
One section per subtest on the current ASVAB: what it tests, how to prepare, which Army line scores it feeds, and how many of the 119 verified MOS use each one. Start with the subtest behind your biggest score gap.
General Science
Biology, chemistry, physics, and earth science fundamentals.
Study tips
- Review the scientific method and basic lab terminology
- Focus on biology (cells, systems) and physical science (forces, energy)
- Know the periodic table basics: element groups and common properties
- Use process of elimination for topics you are less familiar with
Line scores this subtest feeds
- EL Electronics used by 19 verified MOS (thresholds 88–107)
- GM General Maintenance used by 14 verified MOS (thresholds 78–105)
- ST Skilled Technical used by 46 verified MOS (thresholds 85–112)
Arithmetic Reasoning
Word problems that test your ability to solve real-world math scenarios.
Study tips
- Translate the word problem into an equation before solving
- Identify what the question is actually asking: rate, total, difference, or ratio
- Check units: if the question asks for hours, make sure your answer is in hours
- Estimate first to eliminate obviously wrong answers
Line scores this subtest feeds
- GT General Technical used by 30 verified MOS (thresholds 85–110)
- CL Clerical used by 10 verified MOS (thresholds 86–105)
- CO Combat used by 6 verified MOS (thresholds 77–82)
- EL Electronics used by 19 verified MOS (thresholds 88–107)
- FA Field Artillery no verified MOS on this site currently uses this score
- SC Surveillance and Communications used by 2 verified MOS (thresholds 95–102)
Word Knowledge
Vocabulary: choosing the word closest in meaning to a given word.
Study tips
- Use word roots, prefixes, and suffixes to decode unfamiliar words
- Read the word in context if a sentence is provided
- Eliminate answers that are clearly unrelated before guessing
- Build vocabulary through daily reading: news articles, textbooks, or fiction
Line scores this subtest feeds
- GT General Technical used by 30 verified MOS (thresholds 85–110)
- CL Clerical used by 10 verified MOS (thresholds 86–105)
- OF Operators and Food used by 6 verified MOS (thresholds 85–95)
- SC Surveillance and Communications used by 2 verified MOS (thresholds 95–102)
- ST Skilled Technical used by 46 verified MOS (thresholds 85–112)
Paragraph Comprehension
Reading passages and answering questions about main ideas, details, and inferences.
Study tips
- Read the question first, then scan the passage for the relevant section
- Identify the main claim or argument before evaluating evidence
- Distinguish between what the passage says and what it implies
- Avoid answers that are true in general but not supported by the passage
Line scores this subtest feeds
- GT General Technical used by 30 verified MOS (thresholds 85–110)
- CL Clerical used by 10 verified MOS (thresholds 86–105)
- OF Operators and Food used by 6 verified MOS (thresholds 85–95)
- SC Surveillance and Communications used by 2 verified MOS (thresholds 95–102)
- ST Skilled Technical used by 46 verified MOS (thresholds 85–112)
Auto and Shop Information
Automotive systems and shop practices: engines, drivetrains, electrical basics, hand and power tools, fasteners, and materials.
Study tips
- Learn the four-stroke cycle and what each major engine system (fuel, ignition, cooling, lubrication, exhaust) does
- Match tools to tasks: know which wrench, saw, drill bit, or measuring tool fits a job and why
- Understand common fasteners and joining methods (bolts, rivets, welding, soldering) and when each is used
- Spend time in a garage or shop if you can; hands-on familiarity is faster than memorizing lists
Line scores this subtest feeds
- CO Combat used by 6 verified MOS (thresholds 77–82)
- GM General Maintenance used by 14 verified MOS (thresholds 78–105)
- MM Mechanical Maintenance used by 22 verified MOS (thresholds 82–104)
- OF Operators and Food used by 6 verified MOS (thresholds 85–95)
- SC Surveillance and Communications used by 2 verified MOS (thresholds 95–102)
Mathematics Knowledge
Algebra, geometry, and number operations without word problem context.
Study tips
- Review order of operations (PEMDAS) and apply systematically
- Know basic geometry formulas: area, perimeter, volume of common shapes
- Practice factoring and solving quadratic equations
- Work backward from answer choices when direct solving is slow
Line scores this subtest feeds
- CL Clerical used by 10 verified MOS (thresholds 86–105)
- EL Electronics used by 19 verified MOS (thresholds 88–107)
- FA Field Artillery no verified MOS on this site currently uses this score
- GM General Maintenance used by 14 verified MOS (thresholds 78–105)
- ST Skilled Technical used by 46 verified MOS (thresholds 85–112)
Mechanical Comprehension
Mechanical principles: levers, pulleys, gears, springs, fluids, force and motion, and how simple machines trade force for distance.
Study tips
- Master the six simple machines and the mechanical advantage of each
- Work gear and pulley problems by counting teeth or ropes; direction and speed follow from ratios
- Review basic physics of force, torque, pressure, and center of gravity with everyday examples
- Draw the diagram yourself when a question describes a mechanism; most errors come from misreading the setup
Line scores this subtest feeds
- CO Combat used by 6 verified MOS (thresholds 77–82)
- FA Field Artillery no verified MOS on this site currently uses this score
- MM Mechanical Maintenance used by 22 verified MOS (thresholds 82–104)
- OF Operators and Food used by 6 verified MOS (thresholds 85–95)
- SC Surveillance and Communications used by 2 verified MOS (thresholds 95–102)
- ST Skilled Technical used by 46 verified MOS (thresholds 85–112)
Electronics Information
Basic circuits, electrical concepts, and electronic components.
Study tips
- Learn Ohm's Law (V = IR) and power formulas
- Understand series vs. parallel circuits and how they affect current and voltage
- Know common component symbols: resistor, capacitor, diode, transistor
- Review AC vs. DC current and basic transformer principles
Line scores this subtest feeds
- EL Electronics used by 19 verified MOS (thresholds 88–107)
- GM General Maintenance used by 14 verified MOS (thresholds 78–105)
- MM Mechanical Maintenance used by 22 verified MOS (thresholds 82–104)
How subtests turn into scores
You answer questions in 8 subtests. Each is converted to a standard score on a scale where the 1997 reference population has a mean of 50 and a standard deviation of 10. Word Knowledge and Paragraph Comprehension are scored together on the underlying ability scale to produce a single verbal score, VE, which is what the formulas use; it is not WK + PC.
Your AFQT percentile is a lookup on AR + MK + 2 × VE. Your Army line scores (GT, ST, CO, CL, EL, MM, GM, OF, SC, FA) are weighted sums of the seven reported standard scores, each rescaled to a mean of 100 and a standard deviation of 20. The Army score guide walks through each line score, which jobs use it and the range of thresholds it must meet.
One nuance matters for planning: the subtest lists under each line score above are the Army's nominal definitions from DA PAM 611-21. The operational computation, documented by the Defense Manpower Data Center, gives every composite a weight on all seven standard scores, sometimes larger on a subtest outside the nominal list. GT is the only composite that equals its nominal definition exactly. The score calculator shows the operational weights and lets you test what a few more points on one subtest do to every line score.
Ready to practice?
Try a short session drawn from 128 original questions across all 8 current subtests, with explanations for every answer and a fresh set each time.
Start practice →Frequently asked questions
Which ASVAB subtests should I study first?
Start with the subtests that feed the line score your target job requires, and within those, the one where your standard score is lowest. AR, MK and the verbal score VE (Word Knowledge and Paragraph Comprehension) count toward AFQT and toward most Army line scores, so they are the safest default when you have no target yet.
Does improving one subtest raise more than one line score?
Yes. Each Army line score is computed from a weighted sum of seven standard scores, so a higher AR or MK moves several composites at once. The "contributes to" list under each subtest shows the nominal composites; the operational weights in the calculator show that most composites also carry smaller weights on subtests outside that list.
Can I estimate my ASVAB score from practice questions here?
No. Practice sessions on this site, drawn from a bank of 128 original questions, return a raw count of correct answers for study planning. Official scores are norm-referenced and produced by adaptive scoring; a practice count never converts into an AFQT percentile or a line score.
Why are Numerical Operations and Coding Speed not in this guide?
NO and CS are legacy subtests that the current ASVAB no longer administers. They still appear in the Army's nominal composite definitions, but there is nothing to study for them; the Army scores those composites from the subtests that remain.
What is the difference between a standard score and a percentile?
A standard score places your subtest result on a scale with a mean of 50 and a standard deviation of 10 in the 1997 reference population. The percentile next to it tells you what share of that population scored at or below you. Line scores and AFQT are built from the standard scores, not from the percentiles.