Reviewed by Camille G., Founder of Loch Ness Paris · Last updated September 22, 2026

MBTI-style frameworks describe personality using four dichotomies — Introversion/Extraversion, Sensing/Intuition, Thinking/Feeling, and Judging/Perceiving — that combine into 16 distinct personality types. Rather than treating all 16 as an unordered list, most typology systems group them into four temperament families that share a core motivation. Understanding those four families first makes the individual types far easier to place.

What Are the 16 Personality Types?

Each of the 16 types is a unique combination of four letters, one from each of these pairs:

• E or I — Extraversion vs. Introversion: where you draw energy from
• S or N — Sensing vs. Intuition: how you take in information
• T or F — Thinking vs. Feeling: how you make decisions
• J or P — Judging vs. Perceiving: how you approach structure and closure

Four binary choices produce 2⁴ = 16 possible combinations — from INTJ to ESFP. On its own, a four-letter code is just a label. The four temperament families below are what actually give each combination its meaning.

The Four Temperament Families

Most of the descriptive richness in MBTI-style typing comes from grouping the 16 types by their shared N/S and T/F letters (Analysts and Diplomats) or their shared S and J/P letters (Sentinels and Explorers) — a grouping popularized by psychologist David Keirsey’s temperament theory, which predates and heavily influenced today’s typology sites.

🟣 Analysts (NT) — INTJ, INTP, ENTJ, ENTP

Driven by competence, independent reasoning, and strategic thinking. Analysts tend to trust their own analysis over consensus and are drawn to complex problems with a clear, logical structure.

🟢 Diplomats (NF) — INFJ, INFP, ENFJ, ENFP

Driven by values, empathy, and a sense of meaning or purpose. Diplomats tend to prioritize authenticity and human connection, and often gravitate toward causes bigger than themselves.

🔵 Sentinels (SJ) — ISTJ, ISFJ, ESTJ, ESFJ

Driven by structure, duty, and reliability. Sentinels tend to value proven methods, clear expectations, and follow-through — the temperament most associated with dependability.

🟠 Explorers (SP) — ISTP, ISFP, ESTP, ESFP

Driven by direct, present-moment experience. Explorers tend to be adaptable and hands-on, more comfortable responding to what’s happening now than planning far in advance.

Where the Letters Actually Come From

Beneath the four-letter label, MBTI-style theory describes each type as an ordered stack of four cognitive functions — a concept that traces back to Carl Jung’s original 1921 work on psychological types. Each function is either “introverted” or “extraverted,” and every type’s specific stack (dominant, auxiliary, tertiary, inferior) is what actually produces its described traits, not the four letters directly. This is also why two types can share three letters and still feel very different in practice — their underlying function stacks are ordered differently.

How Common Is Each Family?

Based on aggregated self-report data from popular typing platforms — not a scientifically representative population study — Sentinels are consistently the most common family, often cited at roughly 45–46% of respondents, followed by Explorers at around 27%, with Analysts and Diplomats splitting the remaining share. Treat these figures as descriptive of who takes these tests online, not a precise measurement of the general population.

Why Your Result Might Not Be as Fixed as It Looks

Here’s something most typology content leaves out: independent research on MBTI-style scoring has found that 35% to 50% or more of people get a different four-letter type when they retake a standard test within a few weeks — not because they changed, but because of how the scoring works. ^[1] Each of the four dichotomies is actually a continuous trait forced into a binary label; anyone scoring near the midpoint on any of them can flip to the opposite letter from ordinary measurement noise.

We wrote a full breakdown of exactly why this happens, and built a test designed around showing that uncertainty instead of hiding it: Your MBTI Result Has a Coin-Flip Problem.

Explore Each Family in Depth

Each family page covers its 4 types in full, including cognitive functions, careers, and compatibility.

Sources & Further Reading

1. Pittenger, D. J. (2005). Cautionary comments regarding the Myers-Briggs Type Indicator. Consulting Psychology Journal: Practice and Research, 57(3), 210–221. https://doi.org/10.1037/1065-9293.57.3.210
2. Jung, C. G. (1921). Psychological Types. Originally published in German as Psychologische Typen; the source of the original introversion/extraversion and function theory MBTI-style models build on.
3. Keirsey, D., & Bates, M. (1998). Please Understand Me II. Prometheus Nemesis Book Company. Source of the four-temperament grouping (Rationals/Idealists/Guardians/Artisans, popularized as Analysts/Diplomats/Sentinels/Explorers).
4. Myers, I. B., & Myers, P. B. (1980). Gifts Differing: Understanding Personality Type. Davies-Black Publishing.

Disclosure: type and temperament descriptions on this page are generalizations drawn from popular MBTI-style typology, not a clinical diagnostic framework. For a free assessment built on public-domain, peer-reviewed instruments, see our personality test.