The Short Answer
Both tests are accepted by every major college and university in the United States. Neither is preferred by admissions offices. The only question worth answering is which one will give you a better score — and that’s not something any comparison guide can tell you. Only a practice test can.
Test Structure: How They Compare
The SAT and ACT have meaningfully different structures, and understanding those differences is the first step.
The SAT (now fully digital) consists of two sections: Reading & Writing and Math. It uses an adaptive format, meaning the difficulty of the second module adjusts based on how well you did on the first. Total testing time is about 2 hours and 14 minutes, making it the shorter of the two tests.
The ACT consists of three required multiple-choice sections — English (35 minutes), Mathematics (50 minutes), and Reading (40 minutes) — plus two optional sections: Science (40 minutes) and Writing/Essay (40 minutes). While the vast majority of colleges do not require ACT Science or Writing, a small number of schools — including Boston University, Georgetown, and the U.S. service academies — do require Science, and a handful of smaller institutions require Writing. Always check the specific requirements of your target schools. If you take only the three required sections, total testing time is about 2 hours and 20 minutes; adding Science brings it to 3 hours.
Key Differences to Know
Math
The SAT places a heavier emphasis on math — it makes up half of your total score. The ACT Math section covers algebra, functions, geometry, statistics and probability, and number and quantity, including topics like rational exponents, vectors, matrices, and trigonometric ratios. If math is your strongest subject, the SAT’s emphasis on it could work in your favor. If you prefer to spread your score across more subjects, the ACT’s structure may suit you better.
Science — Now Optional on the ACT
This is one of the most important recent changes to know: the ACT Science section is now optional for most students. The section focuses on interpretation of data, scientific investigation, and evaluation of scientific arguments — advanced science knowledge is not required, but background from introductory science courses may help. Students who want their science ability reflected in their score, or who are applying to schools that require it, should plan to take it.
Reading and English
Both tests require strong reading comprehension. The ACT separates these skills into two distinct sections: English (grammar, usage, and rhetorical skills) and Reading (comprehension and analysis). The SAT integrates both into a single Reading & Writing section. Some students find the ACT’s separation more intuitive; others prefer the SAT’s combined approach.
Writing — Also Optional on the ACT
The ACT Writing section is a 40-minute essay in which students develop their own perspective on a complex issue and analyze its relationship to other provided perspectives. Like Science, it is optional for the vast majority of schools — though a small number of institutions still require it. The SAT does not currently include an essay component.
Timing and Pacing
The ACT is generally considered the more time-pressured test. ACT notes that the time limits are designed to give nearly everyone enough time to finish, but pacing yourself carefully is essential. Students who work quickly but sometimes sacrifice accuracy tend to do better on the SAT. Students who are fast and accurate tend to excel on the ACT.
Calculator Policy
On the SAT, the Desmos graphing calculator is embedded in the Bluebook testing app with both graphing and scientific options — students can toggle between the two at any point during the Math section. Students may also bring their own approved handheld calculator.
On the digital ACT, the Desmos graphing calculator is now embedded in the online Math section as well — students can also bring their own approved handheld calculator. The paper ACT remains unchanged — students must bring their own approved calculator. Calculators are not permitted on the ACT Science section in either format.
Desmos tends to be a bigger advantage on the SAT than on the ACT. The SAT’s heavy emphasis on algebra and coordinate geometry aligns particularly well with Desmos’s graphing strengths, while the ACT Math section covers a broader and more varied range of topics.
Who Tends to Do Better on the SAT
- Students who are strong in math
- Students who prefer a shorter, less time-pressured test
- Students who are comfortable working on a computer
- Students who do well with adaptive testing formats
Who Tends to Do Better on the ACT
- Students who are strong across English, math, and reading
- Students who want the option to showcase science ability
- Students who are fast, accurate test-takers
- Students who prefer a traditional paper-based format (a digital option is also available)
- Students already comfortable with Desmos who plan to take the digital version
The Best Way to Decide: Take a Practice Test of Each
The single most reliable way to choose is to take a full-length practice test of each under realistic conditions. Your scores will often tell you more than any comparison guide can. Many students are surprised to find a meaningful difference between their results — sometimes 10 or more percentile points — even when they expected to perform similarly on both.
After taking both practice tests, compare your percentile scores (not raw scores, since the scales are different) to see which test reflects your abilities more favorably.
A Note on Test Prep
Whichever test you choose, targeted practice on specific question types is the most efficient way to improve your score. FreeTestPrep.com has free drills for both tests, organized by section so you can focus your time where it matters most:
- SAT: SAT Math · SAT Reading & Writing · SAT Grammar Rules · SAT Vocabulary Flashcards
- ACT: ACT Math · ACT English · ACT Grammar Rules · ACT Reading · ACT Science
So Which Test Should You Take?
Neither test is objectively harder. Neither is preferred by colleges. The right test is simply the one where you score better — and you won’t know which that is until you sit down and actually try both. Take a practice test of each, compare your percentile results, and let the data make the decision for you. Everything else is noise.