How Weird Is Your Brain?

weirdly accurate.

How Weird Is Your Brain?

How weird is my brain?

Probably weirder than you think, because most people assume their own mind is the standard one. For a century, scientists put crossed senses, such as letters that come with colours, at about 1 person in 2,000. In 2006 Julia Simner’s team in Edinburgh tested ordinary people instead of waiting for volunteers, and found them 88 times more common. This test asks about twelve experiences like that, each with its scientific name and a published figure.

The twelve questions come in a fixed order, in three parts of four: everyday glitches (déjà vu, a word stuck on the tip of your tongue), crossed senses (including the bouba/kiki question, which you answer on the spot by picking a shape) and words and numbers (letters with their own colours, for example). You answer each one yes or no, and straight away you see what the experience is called and how common it is in a published study: Alan Brown’s 2003 review of déjà vu surveys, Ćwiek and colleagues’ 2022 study of 917 speakers of 25 languages for bouba/kiki, and, for synaesthesia, studies such as Banissy et al. (2009), who screened 567 students, and Chun and Hupé (2013), who asked 1,017 people in France. Every yes hangs a piece on a 3D mobile, heavier the rarer it is. At the end you get your count against the average adult’s, your rarest quirk with its name and why it happens, and a playful brain type.

It is not a diagnosis or a psychological test, and none of the twelve is an illness: synaesthesia is a difference in how the senses connect, not a disorder. Each figure comes from a different study with its own people — hospital staff, students, adults in France, speakers of 25 languages — so read them as a rough guide rather than one survey. Your answers are self-reports. For synaesthesia, studies that test people find far fewer than questionnaires do, so a yes here means “I think so”, not a confirmed synaesthesia.

What the test asks

One thing: which of twelve named experiences your waking mind has, and how common each one is.

The task

  • 12 yes-or-no questions in a fixed order, in three parts of four: everyday glitches, crossed senses, words and numbers; tap a button or press 1 or 2
  • Every experience has its scientific name, such as déjà vu, the tip-of-the-tongue state or grapheme–colour synaesthesia, and a figure from a named published study
  • One question, the bouba/kiki effect, you answer on the spot by picking one of two shapes
  • Each yes hangs a painted piece on a 3D mobile in front of a warm white wall; rarer ones hang heavier and tip the mobile further

Your result

  • How many of the twelve you have, next to the average adult’s count of about four, worked out by adding the twelve published rates
  • Your rarest quirk, what it is called and why it happens
  • A quirk-by-quirk sheet with every figure, its source and a sentence on why minds do this
  • A playful brain type based on which of the rarer experiences you have: a name for fun, not a diagnosis
  • A share card and a challenge link that carry only how many pieces you hung and your type, never which ones

Before you start

  • About two minutes; free, no sign-up
  • Answer from your whole life: “ever” counts, not just this week
  • Works on a phone or a computer in a browser with 3D (WebGL) switched on
  • Sound is optional: soft paper and chime sounds, no background music, with a mute button
  • Your answers stay on your device

Questions about brain quirks

Is this test free? Do I need to sign up to see my result?

Yes, it’s free, and there’s nothing to sign up for: no account, no email, no payment. Your result appears on this page the moment you finish, and you can share it or play again straight away.

How do I know if my brain is weird?

Compare it with real people, one experience at a time. Most people assume what their own mind does is what every mind does, which is why crossed senses went undercounted for a century until Simner and colleagues tested ordinary people in 2006. The How Weird Is Your Brain test asks about twelve named experiences and shows, for each one, the share of people in a published study who have it, so you can see which of yours are common and which are rare.

How accurate are the numbers in the brain quirks test?

Each figure is real, but they come from different studies and should be read as a rough guide. Déjà vu comes from Alan Brown’s 2003 review of surveys, phantom vibrations from Rothberg and colleagues’ 2010 survey of 169 hospital staff, and the synaesthesias from screened students and adults in France. The average count of about four comes from adding the twelve rates, which needs no survey of who has which together. The result sheet lists every figure with its source.

Is this a synesthesia test? Can it tell me if I have synaesthesia?

No, it can only tell you that you might. Synaesthesia (also spelled synesthesia) is confirmed in research by testing people, not just asking them, and studies that test, such as Banissy and colleagues’ 2009 screening of 567 students, find far fewer cases than questionnaires do. The test asks about several kinds, such as letters with their own colours and numbers that sit in a shape in space, and shows how common each one is. A yes is a reason to read more, not a result.

How many brain quirks does the average person have?

About four of the twelve in this test. Adding up the twelve published rates gives an average of about 4.2 per adult; an average like that holds even though some quirks tend to come together. Most people have several of the everyday glitches, such as déjà vu and the tip-of-the-tongue state, which Alan Brown’s 1991 review describes as nearly universal and roughly weekly. The rarer, crossed-sense experiences are what make a count stand out.

What is the bouba/kiki test?

The bouba/kiki effect is one of psychology’s best-known questions about sounds and shapes: you see two shapes and decide which one is called “bouba”. In this test you answer it on the spot, before any explanation. After you pick, the page shows how people answered in Ćwiek and colleagues’ 2022 study of 917 speakers of 25 languages using 10 writing systems, and why.

Is this a diagnosis? Is déjà vu a sign that something is wrong?

No. The How Weird Is Your Brain test is not a medical or psychological test, and none of the twelve experiences is an illness. Déjà vu is ordinary and more common when you are young, tired or stressed. If it starts coming often, in spells that feel the same each time, or together with a rising feeling in the stomach, a strange smell or taste, or moments you can’t account for, mention it to a doctor; the NHS page on the symptoms of epilepsy is a calm place to start.

Where the numbers come from

Each experience’s figure is the share of people in the study listed for it on the result sheet, which names all twelve sources; the studies differ in who they asked and whether they tested or only asked. The average of about four adds up the twelve rates. The site does not publish its own players’ data.