Yes, you should (probably) guess!
Now that the New SAT, PSAT, and AP tests have abolished their guessing penalties, the short answer is “yes.” The long answer is still what it was before: it depends on the test. Very few tests today, however, penalize random guesses. A notable exception is the SSAT, a test required for boarding schools and some private schools. For any standardized test, especially more specialized exams, make sure to read the official instructions in case there is a penalty.
When you guess, guess smart.
While the elimination of guessing penalties simplifies your test strategy, it’s still important to “guess smart”:
1) Always eliminate answer choices you suspect are wrong before guessing.
2) Choose a “back-up letter” ahead of time (C works well) and use it every time for completely random guesses. This applies to questions that you purposely skip due to time constraints, as well as questions where you have no idea about the correct answer. The purpose of the back-up letter is to avoid wasting time doing “eenie-meanie-minie-mo” when you could use those few seconds to solve a problem you know how to do.
3) On tests with no guessing penalty, don’t leave any answers blank. In the last minute allowed for each section, fill out any remaining or skipped questions with your back-up letter. For every four guesses, you’re statistically likely to earn one extra point!
4) Don’t overanalyze the answer choice patterns. If you know how to solve the problems, don’t second-guess yourself if you get four Ds in a row or if don’t choose A for the first ten questions. Each letter should average out to be correct about an equal number of times between all the tests and sections, but within an individual test section there are plenty of random patterns that could be 100% correct. Despite myths that “C” is more likely to be correct (which is true on some teacher-made tests), these tests are randomized, so there is no magic letter. Instead of analyzing the letter patterns, look for the best answer to each question.
Work to master the test, not master the guess.
Though the removal of guessing penalties takes some stress out of the test-taking process, the best strategy is to master the content and pacing so you feel confident about the correct answer on as many questions as possible. The best guessing strategy is not to need to guess at all!