In reality, each test has its own set of difficulties. The ACT has significantly more time pressure than the SAT. The ACT also covers more material: More grammar rules, more math topics, and some rudimentary science concepts. On the other hand, the vocabulary on the SAT is tougher, and SAT questions also have a well-deserved reputation for being “trickier” and less straightforward than ACT questions. On balance, these differences between the two tests usually even out. While a small percentage of students will score higher on one test, most students will perform similarly on both tests.