The set of 16 personality types defined by Katharine Briggs and Isabel Myers is probably the most well known and popular personality system. They published the Myers–Briggs Type Indicator in 1944 based on the theories of Swiss psychiatrist Carl Jung. The MBTI measures four independent dichotomies, which combine into 16 different types. A person is one of each of these:

1. Introverted (I) or Extraverted (E)
2. Sensing (S) or iNtuitive (N)
3. Thinking (T) or Feeling (F)
4. Judging (J) or Perceiving (P)

The results for a person on each pair can be combined letter by letter. For example, preferences for Introversion, Sensing, Feeling, and Judging becomes ISFJ.

The OJTS is a free and open-source test designed to produce an equivalent result to the MBTI. It was developed by selecting questions that discriminate between people who already identify as one of the 16 types. So it can be considered to measure the average definition of each type across internet users. It is currently on version 2.1, see the full documentation. In a comparison between several different online tests, the OJTS had the strongest agreement between self reported type and test result.

This test has 48 questions and takes most people 3-5 minutes to complete. The questions come in two sections. In the first section you will be given a series of statements and asked to rate how much you agree that it could apply to you.

You use of this assessment should be for educational or entertainment purposes only. This is not psychological advice of any kind. Additionally, your responses to this questionnaire will be anonymously saved and possibly used for research or otherwise distributed.