HEXACO vs MBTI: What Changes When You Add Two More Dimensions?

What MBTI Measures

The Myers-Briggs Type Indicator, created in the 1940s by Katharine Briggs and Isabel Briggs Myers, is based on Carl Jung's theory of psychological types. It maps personality along four dimensions, each scored as one of two options:

• E or I — Extraversion or Introversion
• S or N — Sensing or iNtuition
• T or F — Thinking or Feeling
• J or P — Judging or Perceiving

Four dimensions, two options each, produce 2⁴ = 16 personality types. The framework became widely popular in workplaces, education, and everyday conversation.

McCrae and Costa, two of the most cited researchers in personality psychology, confirmed that the four dimensions MBTI measures do correspond to real personality traits (McCrae & Costa, 1989). The traits are genuine. The question that followed was whether four dimensions were sufficient.

From 4 to 5: The Big Five

In the 1980s, a different approach to personality emerged. Instead of starting from a theory, researchers started from language.

The reasoning — known as the lexical hypothesis — is that if a personality trait matters to people, languages will have words for it. Researchers collected thousands of personality-describing adjectives, had people rate themselves and others on those words, and used factor analysis to find the structure underneath.

In English, five factors consistently appeared: Openness, Conscientiousness, Extraversion, Agreeableness, and Neuroticism — the Big Five (OCEAN). This became the standard model in academic personality psychology.

From 5 to 6: The Cross-Cultural Discovery

Researchers Kibeom Lee and Michael Ashton applied the same lexical methodology across seven languages: Dutch, French, German, Hungarian, Italian, Korean, and Polish (Ashton et al., 2004).

Five factors weren't enough. A sixth factor emerged consistently across all seven languages: Honesty-Humility.

This dimension captures sincerity, fairness, modesty, and greed-avoidance on one end, versus manipulation, entitlement, and exploitation on the other. Neither MBTI nor the Big Five had a dedicated factor for this. It had been invisible in English-only studies, but appeared clearly once the data included multiple language families.

Lee and Ashton named the six-factor model HEXACO:

• H — Honesty-Humility
• E — Emotionality
• X — eXtraversion
• A — Agreeableness (vs. Anger)
• C — Conscientiousness
• O — Openness to Experience

What Honesty-Humility Predicts

The sixth factor turned out to have significant predictive power for real-world behavior:

• A meta-analysis of workplace behavior found Honesty-Humility to be the strongest single predictor of workplace deviance (theft, absenteeism, sabotage). HEXACO explained 32% of the variance in workplace misconduct, compared to 19% for the Big Five (Pletzer et al., 2019).

• The "Dark Triad" — Machiavellianism, narcissism, and psychopathy — correlated at -0.95 with Honesty-Humility (Lee & Ashton, 2014). This near-complete overlap means that thousands of Dark Triad studies were essentially measuring the low pole of a dimension HEXACO already included.

• Relationship satisfaction, attitudes toward corruption, and status-driven consumer behavior also link to this dimension (Ashton & Lee, 2007).

How HEXACO Reorganizes Existing Factors

HEXACO doesn't just add a sixth factor. It also rearranges how some traits are grouped, based on what the cross-cultural data showed.

Agreeableness splits into two. In the Big Five, "Agreeableness" combines quite different tendencies. HEXACO separates them (Ashton, Lee, & de Vries, 2014):

• Honesty-Humility (H) — proactive fairness: not exploiting others even when you could.
• Agreeableness (A) — reactive tolerance: not retaliating when wronged.

These are distinct. Someone can score high on one and low on the other — scrupulously fair but quick to anger, or easygoing but willing to bend rules for personal gain.

Anger moves. In the Big Five, anger is part of Neuroticism — grouped with anxiety and depression. In HEXACO, anger moves to the low end of Agreeableness. The logic: anger is a retaliatory response, not an emotional vulnerability. HEXACO's Emotionality factor focuses on attachment, empathy, and sensitivity instead.

Side by Side

MBTI and HEXACO serve different purposes. MBTI provides a simple, shareable framework for thinking about personality. HEXACO is a research instrument designed to measure personality structure as comprehensively as current evidence supports.

64 Types

HEXACO's six dimensions, each scored as High or Low, produce 2⁶ = 64 personality types. Each type combines all six dimensions — for example, a profile with high Honesty-Humility, low Emotionality, high Extraversion, low Agreeableness, high Conscientiousness, and high Openness maps to a specific type with its own descriptive name.

The type label summarizes the profile. The underlying scores — shown as a radar chart — provide the detail. Two people with the same type label can still differ meaningfully in their individual dimension scores.

The Trajectory

Personality science has followed a clear trajectory: Jung's clinical observations in the 1920s, MBTI's practical framework in the 1940s, the Big Five's empirical foundation in the 1980s, and HEXACO's cross-cultural expansion in the 2000s.

Each step was built on the previous one. MBTI brought personality into everyday conversation. The Big Five grounded it in data. HEXACO extended the map to include a dimension — Honesty-Humility — that earlier frameworks had missed.

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References:

• Ashton, M. C., Lee, K., Perugini, M., et al. (2004). A six-factor structure of personality-descriptive adjectives: Solutions from psycholexical studies in seven languages. Journal of Personality and Social Psychology, 86(2), 356–366.
• Ashton, M. C., & Lee, K. (2007). Empirical, theoretical, and practical advantages of the HEXACO model. Personality and Social Psychology Review, 11(2), 150–166.
• Ashton, M. C., Lee, K., & de Vries, R. E. (2014). The HEXACO Honesty-Humility, Agreeableness, and Emotionality factors. Personality and Social Psychology Review, 18(2), 139–152.
• Lee, K., & Ashton, M. C. (2014). The Dark Triad, the Big Five, and the HEXACO model. Personality and Individual Differences, 67, 2–5.
• McCrae, R. R., & Costa, P. T. (1989). Reinterpreting the Myers-Briggs Type Indicator from the perspective of the Five-Factor Model. Journal of Personality, 57(1), 17–40.
• Pletzer, J. L., et al. (2019). A meta-analysis of the relations between personality and workplace deviance: Big Five versus HEXACO. Journal of Vocational Behavior, 112, 369–383.