The ASVAB is made up of 10 sub-tests and each of these sub-tests is given a specific two-letter code (for example, General Science is coded "GS").
There are two ways to take the ASVAB: in written form and electronically. The written test consists of 225 questions and has a time limit of about two and a half hours, while the computer version contains 145 questions with a similar time limit.
Once the test is taken and submitted, each section is marked separately. Additionally, all 10 tests are combined to compute a student's score on what is referred to as the Armed Forces Qualification Test (AFQT).
The AFQT score is used only to determine a student's eligibility for enlistment in the Army, Navy, Air Force, or Marine Corps and is marked on a basis of 1-99. To be considered for enlistment, a student needs a score of at least 31.
Scores on each of the ASVAB sub-tests determine what types of military jobs would be available to each test-taker. Each branch of the U.S. Military divides a student's scores into different job categories and calculates the most suitable career choices based on the student's overall score in those categories.
According to the U.S. Military, "Your first priority should be to get as high a percentile score as you possibly can." ASVAB study guides, sample tests, and prep courses are available widely to assist students with the achievement of good results.