What is the Myers-Briggs Type Indicator (MBTI)?

The Myers-Briggs Type Indicator (MBTI) is one of the world’s most widely used personality assessments. Many individuals and teams use it to better understand themselves and each other. From team-building exercises to leadership coaching and career development, MBTI results are often used to support personal and professional growth. But how does this personality assessment actually work, and what do those four personality type letters really mean?

This article explains what the MBTI is, how it categorizes personality types, and why the tool is both popular and debated. It also outlines how validated alternatives, including SIGMA’s Leadership Skills Profile – Revised® (LSP-R®), for organizations seeking a more evidence-based approach to personality and leadership assessment.

What is the MBTI?

The Myers-Briggs Type Indicator (MBTI) is a self-report assessment that groups test takers into 16 personality types based on their tendencies in four categorical dichotomies:

  1. Energy source: Extraversion (E) vs. Introversion (I)
  2. Information gathering: Sensing (S) vs. Intuition (N)
  3. Decision-making: Thinking (T) vs. Feeling (F)
  4. Lifestyle: Judging (J) vs. Perceiving (P)

What Does MBTI Stand for?

MBTI stands for “Myers-Briggs Type Indicator”. The assessment is named after the developers, Katharine Cook Briggs and Isabel Briggs Myers, who based their work on Carl Jung’s theory of psychological types.

What Do the MBTI Letters Mean?

The MBTI personality test assigns letters that represent preferences for recharging, learning, decision-making, and general lifestyle:1

How Common is Each Personality Type?

The distribution of MBTI types in the United States, as of 2024, was as follows:2

Personality TypePercentage
ISFJ13.8%
ESFJ12.3%
ISTJ11.6%
ISFP8.8%
ESTJ8.7%
ESFP8.5%
ENFP8.1%
ISTP5.4%
INFP4.4%
ESTP4.3%
INTP3.3%
ENTP3.2%
ENFJ2.5%
INTJ2.1%
ENTJ1.8%
INFJ1.5%

According to this personality type distribution:

  • The four most common types (ISFJ, ESFJ, ISTJ, ISFP) account for 46.5% of the population.
  • The four rarest types (INFJ, ENTJ, INTJ, ENFJ) make up only 7.9% of the population.
  • Sensing types (S) are significantly more prevalent than Intuitive types (N).
  • Feeling types (F) are more common than Thinking types (T).

How Does the MBTI Work?

Each year, millions of people complete the MBTI. Key features include:

  • Categorization by preference. There are four areas on which individuals are sorted. These four areas interact to produce 16 distinct profiles and each individual is placed into one profile based on their responses. The four areas are Extraversion vs. Introversion, Sensing vs. Intuition, Thinking vs. Feeling, and Judging vs. Perceiving. Responses are dichotomously scored, such that individuals are either “Extraverted” or “Introverted,” “Thinking” or “Feeling,” and so on.
  • Results are delivered by a trained MBTI administrator. The measure is restricted, so it can only be administered, scored, and interpreted by a trained MBTI administrator. While this increases the costs associated with personality testing, it also decreases the likelihood that the results will be misunderstood or misinterpreted.
  • Appropriate use. The MBTI is designed to build awareness of preferences. It is not intended to predict job performance or to support employee selection decisions.

Is the Myers-Briggs Missing Something?

While the MBTI is popular among human resources (HR) professionals, it is frequently criticized by industrial and organizational (I-O) psychologists, who focus on scientific standards for workplace assessment, including validity and reliability. 

In “Goodbye to MBTI, the Fad That Won’t Die”, Dr. Adam Grant questions the validity, reliability, and comprehensiveness of the MBTI and likens it to “a physical exam that ignores your torso and one of your arms.” Lillian Cunningham summarizes academic critiques in “Myers-Briggs: Does it pay to know your type?” noting concerns that MBTI use can resemble belief more than evidence and that interpretation is often delivered by practitioners without formal training in psychological science.

A central criticism of the MBTI, as Grant explains, is that “four letters don’t do justice to anyone’s identity.”  As Grant argues, personality is complex, and a four-letter type can miss meaningful variation within individuals.

Looking for More?

For organizations that want personality insights grounded in stronger psychometric evidence, validated alternatives may be a better fit. SIGMA’s flagship leadership assessment, the Leadership Skills Profile – Revised® (LSP-R®), is one option designed to support leadership development and talent decisions.

Start the Conversation

  1. Melissa. (July 11, 2017). What do the letters in the Myers-Briggs test stand for? MBTI. Retrieved from https://www.mbtionline.com/en-US/Articles/what-do-the-letters-in-the-myers-briggs-test-stand-for. ↩︎
  2. E. Jacobs-Pinson. (November 26, 2024). Myers Briggs Statistics: The 16 Personality Types. Crown Counselling. Retreived from https://crowncounseling.com/statistics/myers-briggs/. ↩︎

About the Author

Glen Harrison

Vice President

Glen Harrison is an organizational transformation consultant and succession planning expert. Over the course of his career, Glen has worked with one-third of the Fortune 500 list and with every level of government in Canada and the United States. Having worked with numerous clients to build robust succession plans from the ground up, Glen has extensive experience in the application of SIGMA’s products and services to help organizations realize their people potential.