What does this test measure?
Short answer: it measures the Big Five personality traits (extraversion, agreeableness, conscientiousness, emotional stability and openness) with items from the International Personality Item Pool (IPIP), plus Honesty-Humility. From those traits it estimates a 4-letter type and, as a fun extra, a “64 types” variant.
The Big Five is the most research-supported personality model. The IPIP is a public item bank created by Lewis R. Goldberg so anyone can measure these traits without licenses. Our In-depth level uses the 50 IPIP Big-Five factor markers.
What is Honesty-Humility (HEXACO)?
The HEXACO model by Kibeom Lee and Michael Ashton adds a sixth trait, Honesty-Humility: sincerity, fairness, low greed and modesty. The official HEXACO-PI-R questionnaire is copyrighted, so we use our own questions inspired by the trait. Treat the result as indicative.
How do the 16 types relate to the Big Five?
Four-letter types (E/I, S/N, T/F, J/P) were popularized by the MBTI®. A classic study by McCrae and Costa (1989) found the four scales map onto four Big Five traits: E/I with extraversion, S/N with openness, T/F with agreeableness and J/P with conscientiousness. The MBTI doesn't measure emotional stability. We compute your type from your traits and show how clear each letter is.
Note: many people score near the midpoint, which is why 4-letter types often change on retest.
What are the 64 personality types (A/O and H/C)?
Short answer: an extension of the 16 types that adds two letters: A (decisive) or O (torn/reflective), and H (warm) or C (reserved). According to Taiwanese media, the Chinese platform APESK created it in 2005. No published scientific studies validate it.
Different sites use the same letters with different names (Assertive/Oscillating, Assertive/Observant, Decisive/Deliberating; Harmony/Calm, Harmonious/Coolheaded, Warm/Reserved). We measure your variant with our own questions and present it as entertainment.
What is the rarest personality type?
The “rarity” rankings of the 64 types seen in ads don't publish sources. For the 16 types, the MBTI manual offers estimates: in a 1998 US sample, INFJ was about 1.5% and ISFJ about 13.8%. Figures vary by country, sex and sample. Rare doesn't mean better.
Frequently asked questions
Is this test free?
Yes. Quick is free with no sign-up, In-depth is free with your email, and Complete costs US$9.99 for the extended report.
Is this the official MBTI test?
No. MBTI® and Myers-Briggs® are registered trademarks of The Myers & Briggs Foundation. Persona64 is not affiliated with or endorsed by it. We estimate a 4-letter type from Big Five traits.
How accurate is it?
IPIP items show good reliability in research, but we don't compare your results with a norm population. Use it as guidance.
Can I use it for hiring?
No. It's an educational and entertainment tool, not designed for hiring or diagnosis.
What does ISTP-AC mean?
ISTP stands for introversion, sensing, thinking and perceiving. AC is the decisive (A) and reserved (C) variant of the 64-type system, which is for fun.
Do you store my answers?
Your answers are stored in your browser so you can resume. We only send data if you give us your email or WhatsApp to receive the report. See the privacy notice.