What is my personality type?

A type puts you in a box: introvert or extravert, thinker or feeler. A trait puts you on a scale: how much of something you have, from very little to a lot. The two ideas make different predictions. If people really came in types, scores would bunch into separate groups with few people in between. If personality is made of traits, most people would sit near the middle, with fewer and fewer towards each end.

That makes the question one that data can answer. Researchers have looked at the shape of scores, at what the type scales actually measure, and at whether people fall into groups when nobody tells them where the lines are.

Defenders of types once pointed to studies in which the scores of a well-known sixteen-type questionnaire seemed to form two humps. A study published in 2002 re-scored the answers of about 12,000 people who had taken it in leadership programmes. The humps turned out to be an artefact of a default setting in the scoring software, which used only 10 points along each scale; with 50, the scores were strongly centre-weighted, like a trait^[1].

In other words, most people scored somewhere in the middle of each dimension. Splitting the middle into two letters puts people who are almost the same on opposite sides of a line.

In a study published in 1989, Robert McCrae and Paul Costa compared that questionnaire with a Big Five questionnaire, using both self-reports and ratings by others, in 267 men and 201 women aged 19 to 93. They found no support for truly two-way preferences or for qualitatively different types. The questionnaire measured four fairly independent dimensions, and those four corresponded to four of the five big personality traits^[2].

Our own type view pairs them this way, scale by scale:

• Introversion and extraversion: the Big Five's extraversion.
• Sensing and intuition: openness.
• Thinking and feeling: agreeableness.
• Judging and perceiving: conscientiousness.
• Neuroticism, the fifth trait, gets no letter at all.

So a four-letter code carries real information, but less than four scores would, and it leaves out how easily you worry or feel stress, which the Big Five treats as a trait in its own right.

Types might exist in a looser sense: some combinations of traits might simply be more common than others. In a study published in 2018, a team of researchers searched four large data sets with more than 1.5 million people for clusters that were denser than chance. They reported robust evidence for at least four types, while noting that the existence of personality types remains extremely controversial^[3].

Other researchers were not convinced. A reply published in 2019 argued, in its title, that the four types may be neither robust nor exhaustive^[4]. Even on the most generous reading, the four were regions where people are more common, with most people between them, not boxes that everyone fits.

A type is usually presented as something you are for life. Traits are steadier than moods, but they do move. A review of 92 samples followed over the years found that people on average grow more conscientious and more emotionally stable, especially between 20 and 40, and that openness rises in adolescence and falls in old age^[5]. A person near the line between two letters at twenty may sit clearly on one side at forty. A score on a scale shows that change; a letter hides it until it jumps.

The honest answer is: probably a mix. Your personality is better described by where you sit on five scales than by one of sixteen labels. If you are near the middle on a scale, which most people are on at least one, a letter for it is close to a coin toss, and a small change in your answers can flip it.

A type is still useful as a quick summary, as long as you read it as one. It is easy to remember and to talk about, and the scales behind it measure real traits. The trouble starts when a label is treated as a fixed category that decides what you are suited for.

• Look at the scale behind each letter, not only the letter.
• Treat a letter close to the middle as both, not either.
• Remember the trait the four letters leave out.
• Expect your answers to shift a little with mood and with time.

Our personality types test is a view of a Big Five result, not a separate questionnaire. It uses the same 120 statements as the Big Five personality test, shows four dials first, and only then gives the closest four-letter code. A dial close to the middle shows both letters. It is not the commercial questionnaire the sixteen types are best known from, and it uses no proprietary type names.

The article on the Big Five versus the sixteen types compares the two side by side.

The five traits themselves, and what research agrees on about them, are explained in the big five personality traits.