INTP stands for introverted, intuitive, thinking, and perceiving, whereas INTJ stands for introverted, intuitive, thinking, and judging. They’re both relatively rare personality types: INTPs make up roughly 3% of the population (and more specifically, 5% of men and 2% of women), while INTJs make up 2% of the population (and are twice as likely to be men as women).
According to Dario Nardi, Ph.D., personality expert and author of Neuroscience of Personality, INTJs typically come across as busy, orderly introverts, who are as innovative as they are hardworking. INTPs, on the other hand, are big abstract thinkers, highly creative, and a bit more “loose” than INTJs, according to licensed therapist De-Andrea Blaylock-Solar, MSW, LCSW-S, CST.
While these two personality types are both introverted, intuitive, and thinking, the primary distinction between an INTP and INTJ is their difference in judging versus perceiving. Judging or perceiving relates to how you approach life, especially when it comes to planning for things to come. Someone with a preference for judging (INTJ, in this case) will feel supported and secure with the help of things like schedules, structure, and clearly defined expectations. A preference for perceiving (INTP), meanwhile, likes flexibility and spontaneity, and may actually be turned off by too much structure and routine.
Check out our full guides to the INTP and INTJ types for the full rundown.