Myers-Briggs

This is the first personality test I took, and it's my personal favorite. The results have been consistent over the years too, which is a good sign that it's working the way it's supposed to work. There are 2 choices for each trait: extroversion or introversion, sensing or intuition, thinking or feeling, and judging or perceiving. While each of these letters make sense with who you are by themselves, the 16 different combination are also very fitting to the people they describe.

Enneagram

I really liked this test, but it was a little long for my liking, and I hate the way that the enneagrams are numbers. Numbers literally mean nothing, so it's hard to remember what is what. However, its descriptions are very accurate, which is why this test has gotten so popular, even though it isn't technically a psychological test.

Love Languages

This test is pretty fun once you've been in a relationship. If you take it before being in a relationship, then you don't really know what you like, so the results are pretty meaningless. But, once you are in a relationship and get accurate results, it's great to know what your (and your partner's) main love languages are, that way you can love them in a way that they know is a sign of love.

Big 5

This test was one of the first for personality tests. While the results are very accurate, with research even corroborating this, it's just not the most enlightening test. It's really helpful in research to know if someone is high on "openness," but it's just not helpful in real life.

Astrology

Although this isn't a personality test, people do use this to analyze their personalities, so I thought I'd include it in the list. Obviously, there is no scientific backing to this "personality test," so accuracy can be pretty lax. However, speaking from personal experience, a lot of it actually seems really correct. I'm not sure how, but it does.

Hogwarts House

Also not scientifically backed, but surprisingly super accurate, is the Hogwarts House quiz. Someone's house tells you more about them than any of these other tests (except maybe the enneagram) because this test shows a person's priorities. For example, Slytherins prioritize goals because of their ambition-oriented minds; Gryffindors prioritize doing the right thing because of their courage; Ravenclaws prioritize learning because of their curiosity; and Hufflepuffs prioritize hard work because of their emphasis on doing their very best.