Considering that the PSAT only costs 18 dollars, and many schools even often offer it for free, it seems like a good idea for many students to take it since they can get practice for the actual SAT. However, the PSAT might not be as good of a practice as you may think. 

The questions on the PSAT were originally made to suit students who were in 8th grade, while the SAT was made originally with 11th-grade level questions. While the PSATs are in the same format and style as the SATs, and they acquaint you with the way of testing, the difficulty of questions can be a massive difference, which makes the PSAT less helpful. Using the SAT practice books would be a better alternative and doing the free online practice tests would help more. 

Spending close to 3 hours taking this test is quite a sacrifice and isn’t worth it. Since it doesn’t prepare as well for the difficulty of questions, only the format of the questions, this can already be practiced for with the practice tests which take much less time then the PSATs, 

On the flip side, research by College Board shows that students who did take the PSAT scored better on average on the SAT than those who didn’t. Also, Collegevine stated the usual increase from a PSAT to an SAT is 50 to 150 points. Since many sources show the PSAT and SAT are correlated in terms of score, this is encouraging to students who do want to take it.

Also, if the format of the PSAT confused a student or the types of questions were challenging, they would know how to solve them better on the SAT, since the format would be the same and they would be familiar with it and better able to understand and solve the types of questions on the test.

Overall, though the PSAT is correlated with success on the SAT in many ways, there are also signs that it can be quite a bit different and not worth it to everybody.