Mental age test: what it measures and how accurate it is

A mental age test usually measures how old your habits and mindset feel, and the closest idea in psychology research is subjective age: how old you feel you are. It is no intelligence test. It is no physical age from a blood test or brain scan either. The trouble: mental age, emotional age and mind age get used interchangeably online. Yet “mental age” began more than a century ago as a term from children’s intelligence testing.

What is mental age? One phrase, four different things

“Mental age” gets used for at least four things: the unit from intelligence testing, subjective age in psychology research, the online quiz, and brain age, which sometimes gets folded in; they measure completely different things.

Searches vary. You will also see emotional age, inner age, soul age and “act your age” in searches, and most of them point to the third row. One popular mental age quiz site says its questions trace back to a Japanese quiz that was popular around 2000, and adds that it has nothing to do with IQ.

The first and fourth are the easiest to mix up. Names are slippery here. “Mental age” sounds like a verdict on how smart you are, because it began as the scoring unit of an intelligence test. “Brain age” also has two very different meanings. Online “brain age tests” are mostly reaction-speed or memory-card games. In neuroscience, brain age means training a model on brain MRI scans to predict how old someone’s brain looks. Cole and Franke (2017) reviewed evidence that a brain that looks older than its owner’s age goes with faster physical and cognitive aging and higher mortality risk, though the measure itself is still debated. A phone game score captures none of it.

How is mental age calculated? It began as a unit for children’s intelligence tests

Mental age was originally the scoring unit of child intelligence scales like the Binet tests: whichever age group’s questions a child could answer set the mental age, so calling an adult “a 12-year-old mentally” has moved far from that usage.

The concept goes back to the intelligence scale that the French psychologists Binet and Simon put together in the early 1900s, hoping to diagnose the intellectual level of children. Later scales grouped questions by age. Simple. An entry in a Taiwanese education encyclopedia gives an example: a child of 8 who answers every question in the 7-year-old group and part of the 8-, 9- and 10-year-old groups works out to a mental age of 8 years 6 months, half a year ahead. Test specialists then divided mental age by actual age and multiplied by 100 to get the early ratio IQ, about 106 for this child.

The same entry states that the unit shrinks with age, so the concept only suits children who are still developing, and adult test scores need to be read another way; modern intelligence tests mostly compare people with norms for their own age. That makes sense. A child changes enormously between 5 and 6. In adulthood, a year is too small a difference to keep counting in “ages.”

If an online quiz asks whether you stay up late or keep up with trends, it is measuring attitude and lifestyle, which have nothing to do with intelligence. In everyday speech, saying someone has a low mental age usually means they do not act like an adult.

Subjective age research: most adults feel younger than they are

In psychology research, mental age usually means subjective age, and large surveys agree that around 25 people switch from feeling older than their age to feeling younger, with the gap widening over time until, after 40, people feel about 20% younger on average.

Rubin and Berntsen (2006) interviewed 1,470 Danish adults aged 20 to 97 at home. On average, people under 25 felt older than their actual age and people over 25 felt younger; expressed as a share of actual age, respondents over 40 felt about 20% younger, and the gap stopped growing after that. Gender, income and education explained almost none of who felt what age. Feeling young is no one group’s privilege.

Chopik and colleagues (2018) collected online data from 502,548 respondents aged 10 to 89 and saw the same pattern: the older the person, the bigger the gap in feeling younger, with the ratio topping out slightly above 20%. They also asked when middle age and old age begin, and the overall averages were about 40 for entering middle age and about 63 for entering old age, with older respondents giving later answers. One explanation researchers offer is that people want distance from negative stereotypes of “old people,” so they resist placing themselves in the category.

Applying the study averages to actual age gives a rough table. Treat it as a sketch. The Danish sample felt about 20% younger past 40, and three US longitudinal samples felt 15% to 16% younger, so the calculation uses 15% to 20%. This is our own arithmetic from averages, not a figure any one study measured, and individuals vary widely:

Subjective age is not a single number either. It splits. Kastenbaum and colleagues (1972) noticed long ago that “how old I look” and “how old I feel” are separate components, which is why an “apparent age” quiz measures something else. Kornadt and colleagues (2018) followed 593 respondents aged 30 to 80 for four years and found that the same person feels a different age in different areas of life, and that those ages change at different speeds.

How do we decide how old we are? Montepare’s (2009) framework proposes that people take an anchor and adjust it by reference points: signals from the body, social expectations about what someone that age should be doing, and the people around them. Everyday life supplies examples. At a high school reunion everyone is talking about mortgages and school districts, and you suddenly feel old; a group of fresh-out-of-college interns uses a meme you do not get, and the same feeling arrives. Your age did not move by a day that night. The reference points did.

Does feeling young mean better health? A link exists, but be careful with cause

Feeling older than your age does go with poorer health and higher mortality risk, but most of that link is explained by illness, inactivity and limited mobility; writing it up as “a young mindset means a long life” overstates it.

Stephan, Sutin and Terracciano (2018) analyzed three national US longitudinal samples, over 17,000 adults in all, mostly middle-aged and older, followed for up to 20 years. On average, respondents felt 15% to 16% younger than their age; people who felt roughly 8, 11 or 13 years older than their age had 18%, 29% and 25% higher mortality risk in the three samples. The later analyses matter more. Disease burden, lack of physical activity, mobility limits and cognitive problems could account for the link between subjective age and death, while depressive symptoms could not. So “feeling old” partly reflects the state of the body. That is worth remembering.

The meta-analysis of Westerhof and colleagues (2014) combined 19 longitudinal studies and concluded that subjective aging has a significant but small effect on health, health behavior and survival; the effect was stronger the shorter the follow-up and the younger the respondents. Mean age in these studies ranged from 57 to 85, with a median of 63.

On brain imaging, Kwak and colleagues (2018) gave MRI scans to 68 healthy older adults: those who felt younger than their age had greater gray matter volume in the inferior frontal and superior temporal gyri, and a younger model-predicted brain age. It is one snapshot in time. It cannot say whether feeling young makes the brain healthier or a healthy brain makes people feel young.

Some news coverage has written this research up as subjective age predicting health better than the date on a birth certificate, leaving out two things: the participants were almost all middle-aged or older, and cause may run both ways. Say you are 23 and a quiz says 45. That number has nothing to do with the mortality figures above. It more likely means you started bringing a thermos to work early.

How does our mental age test work? Four areas, five mind ages

Our Mind Age Test belongs with the fun quizzes: it uses 12 or 30 everyday situations to see how “grown-up” you are across four areas (daily habits, mindset, social style and trend radar), then converts that into a mind age between 14 and 70.

Each question is an everyday scene. The options never change: Yes, Kinda, No. Each option maps to 0 to 3 points of maturity. For most questions, Yes means more grown-up, but 9 questions run the other way; for example, playing podcasts and shows at 1.5x speed makes a Yes lean younger. All the points are added up, divided by the maximum possible and stretched proportionally onto a 14-to-70 scale; that is your mind age.

The quick version has 3 questions per area. The four areas weigh the same. In the full 30-question version, daily habits has 10 questions, mindset 11, social style 5 and trend radar 4; converted by maximum points, the four areas weigh about 32%, 37%, 17% and 14%, so the full version’s mind age is driven mainly by daily habits and mindset.

Your real age stays out of the score. It is only used to compare against your mind age. We checked with our scoring program: the same set of answers gives the same mind age whether you enter 20 or 60.

That is the whole method. The free result shows your mind age, the gap from your actual age and how grown-up each of the four areas is; the full report interprets each area. The quiz is a self-observation tool for fun, with no norms, and it is not a clinical or intelligence assessment.

How accurate is a mental age test? Five things to keep in mind when reading yours

A mental age number works as a snapshot of your lifestyle: it shows which habits lean grown-up and which stay youthful, but it cannot judge a person’s maturity, intelligence or health. The five points that follow come from running our own scoring program.

1. Look at the gaps between the four areas before the total

Two people can both land on 38. One has health-conscious habits and a full trend radar; the other is the reverse. New parents, driven by a baby’s schedule, often go to bed at ten and never leave home without a thermos, so their daily habits lean old; that reflects circumstances, not necessarily mindset.

2. The middle of the scale is about 40

If you answer Kinda to every question on the full version, you get 40; on the quick version, 39. A 25-year-old who picks the middle everywhere would see a mind age 15 years above their real age. That gap says where you sit on this ruler. It does not compare you with people your age. Coincidentally, Chopik and colleagues’ (2018) respondents also put the start of middle age at about 40.

3. The quick version is rougher

With 12 questions, each point is worth about 2 years. Changing a single answer can move the result by 6 to 7 years; on the full version’s 30 questions, each point is under a year. For a steadier number, take the full version. It is worth the extra minutes. Also, answering Yes to everything on the full version gives 53 and No to everything gives 31; because of the reverse questions, pressing the same answer all the way does not send you to either end.

4. An “older” mind age is not a bad one

Many of the questions that raise the score are really about discipline: budgeting, early nights, being the one who sorts out the plans. Stephan, Demulier and Terracciano (2012) studied 1,016 people aged 18 to 91 and found that conscientious people felt more mature even when young; among older people, those who were extraverted, open and healthier by self-rating felt younger. For what these traits mean on the personality map, see What are the Big Five personality traits?.

People also search for “MBTI mental age.” The subjective age research we found mostly uses the Big Five, and we found no reliable work mapping the 16 personality types directly onto mental age. Likewise, a younger social style score, such as feeling awkward eating alone, does not mean you are extraverted; the introversion-extraversion spectrum is covered in What do introvert and extrovert mean?.

5. It changes with life stage

The follow-up by Kornadt and colleagues (2018) shows subjective age shifting within a few years, and shifting differently across life domains. A new job, a move, becoming a parent or retiring all change your routine and your reference points. Try again later. Retaking the quiz six months on and seeing which area moved is more interesting than one number. Trends beat snapshots.

What does an immature mental age mean? Maturity is about owning your own life

When people say someone has a “low mental age” or is “mentally immature,” they usually mean the person has not learned to take responsibility for themselves; in developmental surveys, the standards young people themselves use most to decide someone has grown up are accepting responsibility and making their own decisions.

Arnett (2000) proposed “emerging adulthood” to describe the period from about 18 to 25 when people are no longer teenagers but have not fully taken on adult roles. In the paper he summarizes his own 1990s surveys of Americans: the most important criteria for adulthood were accepting responsibility for yourself and making independent decisions, followed by becoming financially independent. He also notes that this stage exists only in societies that allow young people a longer stretch of exploration.

Seen this way, a youthful spirit and immaturity differ:

Picture a 40-year-old who plays the arcade claw machine after work and pays the mortgage on time has a youthful mindset and is nowhere near a “low mental age.” In reverse, someone with a regular routine whose quiz says 50 may still be unfinished in the emotional department if every argument ends in the silent treatment. A mental age quiz cannot see the latter, which is why it cannot serve as a maturity check.

Want a younger mindset? Four small experiments to start this week

Research has not shown that deliberately feeling young improves health, but subjective age moves with your physical condition, your reference points and how you think about getting older, and each of those leaves you room to act.

1. Catch your age catchphrases. For a week, note how often and where you say “I’m getting old” or “I’m too old for this,” and try swapping in something specific like “I’m tired because I slept late.” Kornadt and colleagues (2018) found that the more negative people’s views of their own future old age, the more their subjective age rose afterward.
2. Move a little more each day. In the analysis of Stephan and colleagues (2018), lack of physical activity was one factor behind the link between feeling old and mortality risk. Getting off the train or bus one stop early and walking, or taking a few flights of stairs at lunch, is the easiest version.
3. Change your reference points. In Montepare’s (2009) framework, the people around you shape how old you feel. Sign up for a community college class, join a workplace club or play a mobile game with your nephew, so your life is not only people your own age.
4. Retake it in six months. After the Mind Age Test, note the four area scores, retake it in half a year and see which one changed before deciding whether to adjust anything.

When to get professional help

If “feeling so old” is really long-term exhaustion, losing interest in things you used to enjoy or poor sleep that is already affecting work or relationships, a primary care doctor, psychiatrist, clinical psychologist or counselor is a good place to start. If your memory has clearly gotten worse and you often forget what was just said, see a neurologist or a memory clinic; an online brain age game cannot replace an exam. If you have thoughts of hurting yourself, call or text 988 (the 988 Suicide & Crisis Lifeline, free, 24 hours a day) or go to the nearest emergency room. In immediate danger, call 911.