IQ Test for Over 40s

Is 40 past your peak?

Not for most abilities. The Seattle Longitudinal Study, which has tracked thousands of adults since 1956, found people performed best on several abilities, including vocabulary, verbal memory, inductive reasoning and spatial orientation, in middle age, roughly 40 to 65.

Two abilities slip earlier: perceptual speed and number skills. Perceptual speed is the one that matters most on this test, because it is timed.

How this test works for over 40s

The test measures fluid reasoning: working out new patterns on the spot. It gives no credit for the knowledge and judgement you have built up, which is the part of intelligence that tends to keep growing through your 40s.

• Expect the timer to feel tighter than it would have at 25. That is normal.
• Reading glasses help. The diagrams have fine detail.
• Use it as a baseline. Retake in a few years and compare your own results, not a stranger's.

What scores mean over 40

On age-normed tests the average stays 100 in your 40s, because you are compared with people your age. Our test scores everyone on one scale, so a typical 45 year old may answer slightly fewer timed questions than a typical 25 year old. In your 40s the difference is usually small.

Fluid versus crystallised intelligence

In the 1960s the psychologist Raymond Cattell split general intelligence into two parts. Fluid intelligence is solving new problems on the spot. Crystallised intelligence is the knowledge and skill you have built up.

Fluid intelligence tends to drift down slowly through adulthood, while crystallised intelligence tends to rise into late middle age. By your 40s the two are pulling in opposite directions, which is why many people feel sharper at work than they would on a puzzle test.