The rarest personality type according to the Myers-Briggs Type Indicator (MBTI) system is the INFJ type, also known as "The Advocate" or "The Counselor." INFJs make up about 1.5% to 2% of the general population, making them the most uncommon personality type overall

. Key characteristics of INFJs include:

• Introversion (I), Intuition (N), Feeling (F), and Judging (J) traits.
• Deep intuition and empathy, often understanding others' emotions and motivations before they themselves do.
• A strong sense of integrity and idealism, seeking meaningful, authentic connections.
• A paradoxical nature: introverted yet caring deeply for others, organized planners who are also dreamers.
• They are rare especially among men, where they constitute about 1%, compared to around 2% among women

Other notably rare personality types include INTJ and ENTJ, each making up about 2% of the population, and ENFJ and ENTP at around 3%

. While some sources mention ESFJ as rare in certain datasets, the consensus in MBTI research and major personality institutes is that INFJ remains the rarest type globally

. In summary, the INFJ personality type is the rarest, distinguished by its unique combination of deep empathy, intuition, and idealism, making INFJs a truly uncommon and distinctive group