The equation for calculating the final score of an ASVAB test is 2 times Verbal Expression plus Arithmetic Reasoning plus Mathematics Knowledge. Verbal Expression is the product of Word Knowledge and Paragraph Comprehension. This score reaches about 300 in the higher ranges, to reach the higher tester percentiles.
Overall score is not based off of the number of questions answered correctly on the ASVAB. The U.S. military uses a weighted system, placing some questions with higher importance than others. Therefore, it is possible to fail several minor questions and still reach a very high score in the test.
The ASVAB has many fields that are scored separately to determine job qualifications. The overall ASVAB score for mathematics and language comprehension is what determines the raw score at the end of the testing process.
The ASVAB test type that is most commonly encountered during the recruitment process is the CAT-ASVAB. This is a computerized test that adapts the questions it gives to a test taker according to their level of ability. Testers that answer many questions correctly will encounter harder and harder questions, which tends to bring their score up dramatically.
The ASVAB is also available even when already in the military. Retaking the test allows military members to change their occupation by qualifying for training and using the test to show their knowledge in the job's qualifying subjects.