Can You Improve Your IQ? (Preview — Not Live)

Q: Is intelligence fixed at birth?

No. A heritability estimate of 50 to 80 percent describes how much of the variation between people in a population is linked to genetic differences — it does not mean any individual's score is locked in. Environment, health, education and life experience meaningfully shape where someone lands within their own range, and that influence continues throughout life — see how much scores vary by country and environment for a sense of scale.

Genetics vs. Environment

Your genes set a range. Your environment picks the point.

Illustration of a DNA double helix, representing the genetic component of intelligence alongside environmental influence

50–80%Adult IQ heritability

Commercial brain-training apps promise to raise your IQ by 15 points. Some older textbooks describe intelligence as fixed at birth, set entirely by genetics. Both claims oversimplify a well-studied area of psychology — the more careful answer depends on what, exactly, you mean by “improve.”

Twin and adoption studies consistently estimate that genetic differences account for roughly 50% to 80% of the variation in adult IQ scores across a population. That range is itself informative: heritability is a statistic about how a population varies, not a ceiling on what any one person can do. Genes are better understood as setting a reaction range — environment (nutrition, education, health, cognitive stimulation) determines where within that range a person actually lands.

Heritability isn’t fixed across the lifespan either. Estimates typically rise from roughly 20% in early childhood toward the 50–80% adult range — a pattern researchers attribute partly to gene–environment correlation: as people grow up, they increasingly choose environments that match and reinforce their own predispositions, which makes genetic influence look larger in the data over time.

See how IQ tests measure this →

The Truth About Brain Training

Near transfer is real. Far transfer is still unproven.

This is the single most misunderstood claim in the brain-training industry — and the one worth understanding before you subscribe to anything.

Play a memory game every day and you will get better at that memory game. That’s near transfer: practicing a specific task improves performance on that task and on very similar ones. It’s well documented and not really in dispute.

The much bigger claim — the one brain-training companies actually sell — is far transfer: the idea that practicing a puzzle game generalizes into broadly higher fluid intelligence or a higher score on an unrelated IQ test. Large reviews, including Owen and colleagues’ widely cited study of over 11,000 participants and Melby-Lervåg & Hulme’s meta-analytic work, have found robust near transfer but little to no evidence of far transfer to general cognitive ability.

In practical terms: brain-training apps are good at teaching you to play brain-training apps. Building genuine reasoning skill looks more like direct, varied engagement with the actual problem types — pattern completion, verbal analogies, numerical reasoning — rather than one repeated game format. Our IQ Tests hub breaks down all eight formats so you can see how each one differs before you take one.

Near transfer: well-supported

Deliberate practice reliably improves performance on the specific skill and task format you train on.

Far transfer: still contested

Generalized gains in fluid intelligence or unrelated IQ tests are not consistently supported by large meta-analyses.

What apps mostly train

Familiarity with a game’s specific format and rules — not a broad increase in the underlying ability a test is meant to measure.

The Flynn Effect

A century of rising scores — and a recent plateau

Named after researcher James Flynn, the Flynn Effect describes one of the most striking findings in 20th-century psychology: average IQ test scores rose by roughly three points per decade across many countries, driven by better nutrition, reduced childhood disease, expanded schooling, and richer, more visually complex environments.

That trend hasn’t continued everywhere. Since around the 1990s, researchers studying Norway, Denmark, the UK, France and several other developed nations have documented a plateau, and in some cases a slight reversal, in these secular gains — sometimes called the “negative Flynn Effect.” Leading explanations point to a ceiling on the environmental gains that drove the original rise, alongside shifts in schooling style, family size and media consumption. It remains an active, unsettled area of research, not a fully solved question.

~3 ptsPer decade

Roughly the average rise in IQ scores documented across much of the 20th century.

1990sPlateau begins

Several developed nations start showing flattening — or slightly declining — scores from around this point.

UnsettledWhy it’s slowing

Researchers debate whether the gains simply saturated or reflect real shifts in environment and education.

Age & Cognition

How fluid and crystallized intelligence change across life

Psychologists split general cognitive ability into two broad components that age very differently.

Fluid intelligence (Gf) is the ability to reason through novel problems without relying on prior knowledge — pattern recognition, abstract logic, working with information you’ve never seen before. Research using the Cattell–Horn–Carroll (CHC) framework consistently finds it peaks in the mid-20s and then declines gradually across adulthood.

Crystallized intelligence (Gc) — accumulated knowledge, vocabulary and learned expertise — behaves almost oppositely: it tends to keep growing well into the 50s and 60s, since it reflects what you’ve learned rather than raw processing speed. This is why standardized tests weigh both components rather than either alone; a purely fluid-reasoning test would unfairly penalize older adults for something that isn’t really a deficit in overall intelligence.

Figure 1. Illustrative lifespan pattern based on Cattell–Horn–Carroll (CHC) theory of cognitive aging: fluid reasoning (Gf) peaks earlier, crystallized knowledge (Gc) later. The curve shapes reflect the general research consensus, not exact scores — they are not derived from individual test data and don’t represent the norming tables of any specific assessment, including ours. See how age-based norming works in practice on our IQ and Age →

Neuroplasticity — the brain’s ability to reorganize itself in response to learning and experience — continues throughout life. It’s a major reason ongoing engagement with new material at any age has a measurable relationship with maintained fluid processing, even though that isn’t the same claim as “raising your IQ.”

Evidence-Based Strategies

What actually helps cognitive function

None of these promise a higher IQ score. All of them are well-supported ways to help your brain perform closer to its own ceiling.

Aerobic exercise. Regular cardiovascular activity is associated with increased brain-derived neurotrophic factor (BDNF) and new neuron growth in the hippocampus, a region central to memory.

Sleep quality. Deep sleep consolidates memory and supports the glymphatic system, the brain’s process for clearing metabolic waste — both tied directly to next-day cognitive performance.

Learning a genuinely new skill. A language, an instrument, or any complex new discipline builds new neural pathways more effectively than repeating a familiar game, because novelty — not repetition — is what drives adaptation.

Direct reasoning practice. Working through the actual logic behind pattern-completion and matrix-style questions — not just guessing — reduces cognitive friction and helps you demonstrate your genuine reasoning ability on a test. Our Culture-Fair IQ Test isolates exactly this kind of abstract, pattern-based reasoning, free of language or number-heavy questions.

Questions

Frequently asked

Can brain-training apps raise my IQ score?

They can improve performance on tasks that resemble the app’s own games — that’s near transfer, and it’s well supported. There’s little reliable evidence that this generalizes into a higher score on an independent, standardised measure like our IQ test or a broad increase in general intelligence.

Does practicing IQ test questions actually help?

Yes, in a specific sense: working through logical, verbal, numerical and spatial reasoning questions with full explanations teaches you the rules behind common formats — pattern transformations, analogies, number series — so you can demonstrate your existing reasoning ability more fully. It’s a familiarity effect, not a way to manufacture new cognitive capacity. Our IQ Tests hub breaks down each format so you know what you’re actually training.

Is intelligence fixed at birth?

No. A heritability estimate of 50–80% describes how much of the variation between people in a population is linked to genetic differences — it doesn’t mean any individual’s score is locked in. Environment, health, education and life experience meaningfully shape where someone lands within their own range, and that influence continues throughout life — see how much scores vary by country and environment for a sense of scale.

What’s the single most effective way to protect cognitive function as you age?

No single intervention is a cure-all, but the combination with the strongest evidence behind it is regular aerobic exercise, consistent sleep quality, and ongoing engagement with genuinely new, challenging material — see our IQ and Age tool for how these effects show up across the lifespan.

What is the Flynn Effect, and does it mean each generation is getting smarter?

The Flynn Effect is the documented rise in raw IQ test scores across generations, roughly three points per decade through most of the 20th century, driven by better nutrition, education and unfamiliarity with test-like reasoning becoming rarer. It doesn’t mean each generation is more intelligent in some deeper sense — it’s why tests are periodically renormed against a fresh sample. See how norming works in our IQ Test Guide.

Does age change how an IQ score is calculated?

Yes. Raw performance is compared against a norm group of a similar age, because fluid reasoning speed and crystallized knowledge shift across the lifespan in different directions. A 70-year-old and a 20-year-old with the same raw answers correct will not receive the same score. Our IQ and Age tool breaks down how norming adjusts for this.

Can stress, poor sleep or a bad testing environment temporarily lower my score?

Yes, and this is one of the most common reasons a retest comes back different. Acute stress, sleep deprivation, illness, or a noisy and distracted testing environment all reduce working memory and processing speed on the day, independent of underlying ability. See our IQ Test Accuracy page for how much day-to-day variation to expect.

Is IQ the same thing as personality, motivation or effort?

No. IQ measures reasoning ability in specific domains — verbal, numerical, spatial and abstract pattern recognition — while personality traits like conscientiousness or openness measure how someone characteristically behaves. The two are only loosely correlated and predict different outcomes. We break this distinction down fully on our IQ vs Personality page.

How can I see whether my score has genuinely changed over time?

Track results from full retests spaced at least a few months apart rather than back-to-back attempts, which mostly reflect familiarity rather than ability. Our IQ Score Over Time tool plots multiple results on one chart, and IQ Comparison shows how a given score sits against different reference groups.

What is regression to the mean, and why does it matter if I retake the test?

If you scored unusually high or low on a first attempt, chance and off-day factors likely inflated that extremity, so a retest tends to land closer to your true average even with no real change in ability. This is regression to the mean, and it’s a major reason an extreme first score should not be treated as your fixed number. See how it plays out in practice on our Regression to the Mean page.

Do children’s IQ scores predict adult intelligence, or do they change a lot growing up?

Childhood scores correlate with adult scores, but the correlation strengthens considerably with age — a test at age 5 predicts adult IQ far less reliably than one at age 15, because cognitive abilities are still developing and consolidating. This is why children’s tests use age-specific norms rather than the adult scale. Our Kids IQ Test is built around age-appropriate norming for exactly this reason.

Does a small change in score actually mean anything?

It depends heavily on where you sit on the distribution. Because IQ scores are normally distributed, a five-point shift near the middle of the curve moves your percentile only slightly, while the same five-point shift far out in either tail can represent a much larger percentile jump. Our IQ Bell Curve page shows how score and percentile relate at different points on the distribution.

Can You ImproveYour IQ?