The SAT is a globally recognized college admission test that lets you show colleges what you know and how well you can apply that knowledge. The SAT doesn’t test logic or abstract reasoning.
Subject Tests are hour-long, content-based tests that allow you to showcase achievement in specific subject areas where you excel. These are the only national admission tests where you choose the tests that best showcase your achievements and interests.
The ACT is a curriculum-based test on the knowledge a student accumulates in high school: English, Mathematics, Reading, and Science. The ACT Plus Writing includes the four subject area tests plus an optional 30-minute Writing Test.