The AP Computer Science A exam:
a complete guide

The short version

AP Computer Science A gives you 42 multiple-choice questions in 90 minutes and they carry 55% of your grade. That works out at more than two minutes a question, which is the most generous rate of any AP exam we publish.

Just over half. And it is the half you can practice on a screen with instant marking, which matters more in this subject than in any other, because the free-response half needs a human being to read your code.

The section, unit by unit

Four units: using objects and methods, selection and iteration, class creation, and data collections. Data collections and selection and iteration together are two thirds of the section, and arrays are where most of the difficulty concentrates.

Unit	Questions	Time
Using Objects and Methods	8	17 min
Selection and Iteration	13	28 min
Class Creation	6	13 min
Data Collections	15	32 min
Total	42	90 min

Every unit works out at roughly the same 129 seconds a question. That is not a scheduling detail. The real exam does not divide its clock by unit at all: you are handed 90 minutes and left to spend them, and a student who sinks four minutes into one hard item has not lost four minutes, they have lost the easy questions at the end they never reached.

What nobody explains about the 1 to 5

Students spend a year chasing a 5 without ever being told what a 5 is. It is not a percentage. Your multiple-choice performance and your free-response performance are each weighted, added into one composite score, and that composite is cut into five bands.

The cut points are set after the exam, every year, by the College Board. They move. A composite that earned a 4 one year can earn a 5 the next, and the reverse. This has two practical consequences: any chart online telling you that 5 starts at a particular percentage is guessing, and a harder-feeling exam is not bad news, because everyone else found it hard too and the bands adjust.

Nothing is deducted for a wrong answer

There is no guessing penalty on any AP exam. A blank scores exactly what a wrong answer scores, which means leaving a question empty is throwing away a one-in-four chance for no reason at all. Mark something as you go rather than promising yourself you will come back, because on a section this tightly timed you will not.

The part experienced teachers know and beginners do not

The uncomfortable truth about this section is that most wrong answers are not misunderstandings. They are tracing errors. A student who understands nested loops perfectly still gets the question wrong because they lost track of what i was on the third pass. The fix is mechanical and unglamorous: write each variable's value down the margin as you read, every single time, until you no longer need to. Students resist this because it feels like something a beginner does. It is what the people scoring fives do.

The commonest way students prepare wrongly

Preparing by writing programs. Writing code and reading someone else's code are different skills, and this section is entirely the second one. A student who has built three projects and never traced a hostile loop is not ready for it.

A revision plan that fits the weighting

Trace before you code. Take twenty loops out of past questions and write the variable values down the margin for every one, even the ones you are sure of, until the habit is automatic. Then move to arrays and ArrayLists, because data collections and selection and iteration are two thirds of the section between them. Sit a full 42-question paper in one 90-minute block at least twice: the clock is generous per question, which tempts students into sinking ten minutes into a single 2D array item, and that is the failure mode this exam actually punishes.

What this practice exam is, and is not

No AP exam is entirely multiple choice, and AP Computer Science A is no exception. The multiple-choice section is 55% of your total score. The rest is four free-response coding questions in 90 minutes: methods and control structures, class design, array and ArrayList work, and 2D arrays.

Our practice exam is the multiple-choice section only, because that is the part a computer can mark honestly and explain question by question. We would rather say that plainly than sell you something described as a full AP Computer Science A exam that is not one. If you plan your revision around us alone, you are planning around 55% of the exam.

What a good score is actually worth

A 5 does not automatically become college credit. Every college sets its own policy, and the policies differ in three ways that matter: which score they require, whether they grant credit or only placement, and whether the credit counts toward your degree or only toward a requirement.

Computer Science A credit varies more than almost any other subject, because departments disagree about whether a 5 covers their first course or only part of it. Some grant credit, some grant placement into the second course without credit, and some grant nothing but let you skip a prerequisite. Check the department's page, not the college's general AP table, since the two often disagree.

What we found when we tested our own exam

Computer science students are the group most likely to assume a practice question is correct because the code compiles in their head, and the least likely to check whether the answer key itself has a pattern in it.

So we measure it. Across the 4 sections of our AP exams long enough to measure (90 questions, in sections of 20 or more), the best score any length-based strategy reaches is 38%, against the 25% that guessing alone should give. Four strategies are scored: pick the longest option, pick the shortest, cross off the longest and guess, cross off the shortest and guess.

Computer Science A options are often fragments of code, which resist padding, and the measured figure reflects that.

The figure comes from the live question bank, produced by the same script that fails our build if any section crosses 40%. AP is the line where this mattered most to us: when we first measured it, picking the longest answer scored 96% on AP World History. We took all four AP families off sale, rewrote them, and put them back. We are telling you the old number as well as the new one, because a company that has never measured this can give you neither.

Where to practice

We publish two AP Computer Science A forms with no questions shared between them, so a second sitting measures what you learned rather than what you remembered, and both unlock together for five credits. Every wrong answer carries its own explanation saying what a student who picked it was probably thinking, which is the part that turns a score into something you can act on. There is a free sample on the samples page if you want to see the format before paying for anything.

Our shorter guides go further on what is on the AP Computer Science A exam and pacing the multiple-choice section.

Common questions

How many multiple-choice questions are on the AP Computer Science A exam?

42, in 90 minutes, which is about 129 seconds a question. That section is 55% of your total score.

What is the rest of the AP Computer Science A exam?

The free-response section: four free-response coding questions in 90 minutes: methods and control structures, class design, array and ArrayList work, and 2D arrays. It carries the remaining 45%.

How is an AP score of 1 to 5 calculated?

Your multiple-choice score and your free-response score are weighted, added into a single composite, and the composite is cut into five bands. The cut points are set after the exam each year, so the raw total needed for a 5 is not fixed and there is no published percentage.

Is there a penalty for guessing on an AP exam?

No. Nothing is deducted for a wrong answer on any AP exam, so a blank and a wrong answer score the same. Every question should carry an answer.

Does your practice exam cover the whole AP Computer Science A exam?

No. Ours is the multiple-choice section only, which is 55% of the real score. The free-response section needs a human reader and we do not pretend to provide one.