Both the SAT and the ACT are multiple-choice tests about three hours in length, including breaks. The SAT is composed of three sections: Math, Critical Reading and Writing. The writing portion of the SAT exam is a 25-minute essay. The ACT has four sections: English, Math, Reading and Science. While there is no mandatory essay section, the optional ACT Writing test provides a parallel to the SAT's written portion. Both tests are administered many times a year.
While comparable in difficulty, the ACT and SAT differ in the type of knowledge being measured. The ACT is primarily a content-based test, focusing on facts and background knowledge. The SAT Reasoning Test instead seeks to measure problem-solving and critical thinking, with less emphasis on content knowledge. In reality, both tests involve content and reasoning to some degree. The ACT covers higher-level material, including trigonometry and science, which the SAT does not address. Instead, the SAT boasts more tricks, logic puzzle and vocabulary questions.
Most colleges and universities require the SAT or the ACT for their admissions, to help them predict student achievement and compare applicants. Nearly all colleges which require a standardized test accept both the SAT and the ACT. Certain schools may have a preference for one test or may convert the scores to their preferred format using a mathematical equation. You can obtain this information by visiting a college's website or contacting the admissions office. In general, private schools or colleges in coastal states tend to prefer the SAT. Colleges in the middle of the country and public universities are more likely to prefer the ACT.
The decision to take the SAT or the ACT depends on each individual student and the colleges she is applying to. Fortunately, both are fairly similar and most students do equivalently on either test. Students who are confident in their educational background, including in science, might consider the ACT easier. Those who prefer reasoning and logic-based questions or who are less confident about their content knowledge may be better served by the SAT. For many students, the mandatory writing section in the SAT serves as the deciding factor between the two tests. However, as more schools require students to take the optional ACT writing portion, this distinction grows less important. No matter which test a student chooses, his scores are an important factor in the admission process.