Practice tests for the SAT and ACT undergraduate admissions tests, and also for the preparatory PSAT, are available online. Graduate-level admissions practice tests available online include the Graduate Record Examinations test, the Medical College Admission Test, the Law School Admission Test and the Graduate Management Admission Test.
KapTest.com and PrincetonReview.com offer practice tests for all of these exams. Both companies requires students to register in order to take a practice exam. SAT.CollegeBoard.org offers practice tests for each section of the SAT. ACTStudent.org's site provides sample ACT test questions.
Although not an admissions test, some colleges use the ACT Compass tests to place students in courses appropriate to their level of learning. ACT.org offers sample questions for the Compass test. This test will be phased by the end of 2016.