ACT vs SAT: What are the differences?

When it comes to the ACT vs. the SAT, both exams are universally accepted by U.S. colleges, which is why students are often unsure of which one they should take.

To help you decide it's important to understand the differences between the two.

Both college admissions exams are popular. In 2018 over 2.1 million test-takers completed the SAT and 1.9 million students took the ACT. It is unclear how many students took both, but experts say it is common for students to sit both.

The idea behind both exams is similar: to demonstrate college readiness. But despite similar aims, the tests vary in a number of ways that we outline below:

1. Time

The SAT test takes three hours, though with an optional 50-minute essay, the time adds up to almost four hours total.

The ACT lasts two hours and 55 minutes, though a 40-minute optional writing test takes it to just over three-and-a-half hours.

The SAT features 154 questions vs. 215 for the ACT, you will have more time on the SAT with 1 minute and 10 seconds per question, compared with 49 seconds on the ACT.

2. Scoring

The scoring for each test also differs. For the SAT, total scores range from 400-1600.

For the ACT, the composite score is between 1 and 36.

These do not include the optional essays, which are scored separately in each exam.

3. Cost

The cost of the exams also varies. The SAT costs $47.50 for the test only and $64.50 if the optional essay is included.

The ACT costs $50.50 for only the exam and $67 if the optional writing test is included. Additional fees may apply for other options, such as late registration.

Students may also be able to take the SAT or ACT for free thanks to state support or fee waivers.

Both exams are offered by nonprofit organizations. For the SAT, this is the College Board, which also offers Advanced Placement courses and other testing services. The ACT organization is more limited in scope, and is centred around the test it offers more than anything else.

4. Science section

The ACT contains a section entirely devoted to science, whereas the SAT does not. 

The ACT Science section contains 40 questions and lasts 35 minutes. Like the other three ACT sections, Science comprises one-fourth of your total ACT score. So if you love science, then a section focused on scientific data, graphs, and hypotheses might appeal to you in the ACT.

However, it's important to remember that the SAT still tests scientific concepts, just not via a separate Science section. 

On the SAT, you’ll occasionally come across questions dealing with scientific passages, data, and charts in the reading, writing, and math sections.

5. Math subsection with no calculator allowed

Unlike the ACT for which you may use a calculator on all Math questions, the SAT contains a Math No Calculator subsection for which you may not use a calculator. 

Consisting of 20 questions, the No Calculator subsection is a mere 25 minutes long, making it the shortest section on the SAT. In contrast, the Math Calculator subsection is 55 minutes long and consists of 38 questions.

As a result, if you struggle with solving math quickly or without a calculator, you'd probably fare better on ACT Math than you would on SAT Math.

However, if you’re confident in your math skills and can work fast without a calculator, the SAT is a solid option.

Realise that on both the ACT and SAT, you can technically solve all math questions without a calculator. This menas the No Calculator questions aren't all that different from Calculator questions.

It's important to realise that the No Calculator questions are meant to be easier to solve without a calculator and so they are generally more reason-based than arithmetic-based.

6. Math content

The ACT and SAT both emphasise algebra (not good news if you aren't a maths lover). However, the ACT also tests some concepts that the SAT doesn’t deal with so much.

First of all, the ACT focuses more on geometry, which makes up about 35-45% of the ACT Math section.

In contrast, geometry accounts for less than 10% of SAT Math questions. You'll also find that trigonometry accounts for about 7% of the ACT but less than 5% of the SAT, so the ACT features more trigonometry.

The ACT also tests things that the SAT doesn’t assess at all, such as matrices, graphs of trigonometry functions, and logarithms.

This means that if you excel at algebra and data analysis, you’ll likely do well on the SAT. But if you prefer trig functions and geometry, and are happy with matrices and logs, the ACT is a better option.

7. Reference guides for formulas

The SAT provides you with a diagram of math formulas, whereas the ACT does not. 

Although all these formulas and laws relate to geometry (which doesn't actually make up much of the SAT), having this diagram to hand means you won’t need to spend lots of time memorising formulas. However, it's a good idea to try and memorise some important formulas not included in the diagram.

Unlike the SAT, the ACT doesn’t give you any formulas on test day, which means you must memorise all possible formulas before taking the test. 

So if you’re worried you might forget some of your formulas, the SAT may be a better choice for you.

8. Math answer choices and score importance

The two tests also differ in the number of answer choices they give you on Math.

Both the SAT and ACT Math sections are mostly multiple choice, but the ACT Math gives you five possible answer choices (A-E or F-K) for each question, whereas the SAT Math only gives you four (A-D).

Fortunately, both tests use rights-only scoring, which means you won't lose a point for an incorrect answer. So if you were to guess an answer to a SAT Math question, you’d have a 25% chance of getting the question right. But if you guess an answer on a ACT Math question, you only have a 20% chance of getting it right.

Therefore, if Math isn't your strong point and you think you may have to guess some answers, remember that the SAT provides a slight advantage over the ACT, with a 5% higher probability of getting a question correct.

You should also consider the importance of your Math score on your overall score.

On the ACT, Math accounts for a quarter of your total score (your Math section score is averaged with your other three section scores). On the SAT, however, Math accounts for half of your total score, making it twice as important.

So if Math isn’t one of your strengths, consider opting for the ACT. With the ACT, a lower Math score won’t negatively affect your total score as much as it will on the SAT. This means you’ll have a better chance at achieving the total percentile you want on the ACT than you will on the SAT.

9. Multiple choice questions

If you like multiple choice questions, especially Math ones, you might want to stick with the ACT.

The SAT, though mostly multiple choice, has student-produced response questions, or grid-ins, which are Math questions for which you must fill in your own answer, i.e. you'll have no answers to choose from.

Grid-ins account for 22% of SAT Math, or 13 total questions across the No Calculator (five grid-ins) and Calculator (eight grid-ins) subsections.

However, the ACT Math only has multiple-choice questions. 

So if you don't like the thought of Math questions without multiple choice answers, then the ACT is a more favourable choice.

10. Reading questions

If you enjoy identifying areas in texts to support your answers to questions, the SAT could be a good option for you.

Evidence-support questions form a large part of SAT Reading but don't feature at all in the ACT Reading.

These questions build on previous ones, and ask you to cite specific lines or paragraphs as evidence for your answer.

Evidence questions can be difficult, especially if you’re not sure where you found your answer in the passage. So if you're not keen on the thought of related questions, try the ACT instead where the Reading questions are all completely separate from each another.

On SAT Reading, all questions given to you follow a chronological order—that is, in the order of the passage to which they refer. But on ACT Reading, questions can flow randomly and do not routinely follow the order of the content in the passages.

As a result, SAT Reading questions are generally easier to follow and thus easier to answer than ACT Reading questions. 

Chronologically ordered questions can also save you time on the SAT, as you won’t need to search the entire passage for the area to which a question is referring.

11. The essay

The final difference between tha ACT and the SAT relates to the essay. Although this is an optional component on both tests, what you actually have to write about will be different.

On the SAT, you'll be given a passage, which you must read and then analyse. Your essay will pull apart the author's argument using evidence and reasoning alone (and not your personal opinion).

On the ACT Writing section, however, the task is different. For this you will have to read a short passage about an issue and then look at the different perspectives. However, unlike the SAT Essay, you'll also be able to give your opinion.

Which essay type is easier for you depends on what you're better at and more comfortable with writing. With the SAT, you'll need to have good reading comprehension skills in order to fully realise the strengths and weaknesses of the author's argument.

With the ACT, you need to be able to effectively compare and contrast different perspectives on an issue as well as give solid evidence to support your own opinion.

Should I do the optional essay?

Experts have different views on whether or not a student should take the optional essay.

Some will advise against it, since many colleges no longer require or recommend it.

But others will argue you should take it, in case you find out it is actually a requirement at the college(s) you are applying to.

However, unless you really struggle with writing, it's probably a good idea to take the essay so that can be an extra data point that colleges have to assess you by.

Recent data show that the majority of students complete the optional essay for each exam.

More than 1.4 million test-takers from the class of 2018 opted for the SAT essay, according to College Board data.

For the ACT, 903,603 students from the class of 2018 took the essay.