What are the differences between ACTs and SATs? (From Quora)

​https://www.quora.com/What-are-the-differences-between-ACTs-and-SATs/answer/John-Linneball

The “new SAT” that came out in 2016 is almost a complete copy of the ACT. The main differences are in the lack of a “science” section on the SAT, some slight differences in the math sections, and differences between the optional essays.
The SAT has graphs and charts to interpret in the reading and writing sections to make up for the lack of a “science” section. Since the ACT “science” section is mostly the “Can you interpret a graph or a chart?” section, and some SAT reading and writing sections are science-based, that’s not a bad substitute.


The math sections differ in that the SAT has two sections - one “calculator,” and one “no calculator,” whereas the ACT has one long section where calculator use is permitted. The SAT problems involve more creativity and thought - or to put it more negatively, involve more “tricks.” The ACT math section involves doing 60 questions in 60 minutes. They’re more straightforward than SAT questions.
Both tests will give you “fill in the formula” questions for complex formulas, to see if you can manipulate equations and substitute in values. The SAT has the same little formula box in at the beginning of both sections, in which basic geometric formulas are printed, as well as some other basic math formulas. The ACT expects you to know the basic formulas.


The optional essays for the tests differ. The ACT presents you with a description of an issue, along with three perspectives on that issue. Your job is to write an essay discussing all three perspectives, then explaining your own perspective, which could be agreeing with one of the perspectives, partially agreeing with one or more, or presenting an entirely different perspective.
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The SAT presents you with a persuasive essay of some sort, usually a newspaper or magazine editorial. Unlike the ACT prompt, the SAT prompt does NOT ask for your opinion on the subject of the essay, but instead asks you to analyze how the author uses facts, rhetoric, and logic to present his or her case. It helps to know the meanings of the words “ethos,” “pathos,” and “logos.”
That’s about it - hope this helps!