ICAR-16: a free eight-minute test of reasoning
Sixteen items, four kinds of puzzle, one percentile you can compare against other people. No account, no email, and every answer you give stays on your own device.
About eight minutes. You can leave and come back; the run resumes where you stopped.
What it measures
The ICAR-16 is a short measure of fluid reasoning, the part of ability that shows up as spotting the rule in a series, finishing a sentence, or rotating a shape in your head. It is not a personality test and it is not a diagnostic tool. Sixteen items, four in each of four kinds:
- Verbal reasoning, four items, where a missing word has to follow from the sentence around it.
- Letter and number series, four items, where the rule behind the sequence has to be found.
- Matrix reasoning, four items, where one panel of a grid is missing and the pattern decides which one fits.
- Three-dimensional rotation, four items, where the same object is shown turned and one view does not belong.
What you get at the end
- A raw score out of sixteen, and a percentile from a reference sample of about 169,000 people.
- A per-item review: which items you got, which you missed, and how hard each item was in that sample.
- A subscale reading for each of the four kinds, so a strong verbal score and a weak spatial one are visible as different things.
What it is not
It is not an IQ test, and the page will not give you an IQ. No published formula converts an ICAR-16 score into an IQ. The ICAR agrees closely with the WAIS-IV Full Scale IQ (r about .81, corrected, N=97), which is why a comparison is worth showing at all, but an agreement between two tests is not a conversion, and a number presented as your IQ would be invented. What is measured is the percentile, from the SAPA reference distribution, and that is what the results page reports.
It is also not a measure of what you know, your education, or your worth. It is sixteen puzzles, once.
Try one item
Continue the series: 2, 6, 12, 20, 30, …
36 38 40 42
Answer: 42, because the differences are 4, 6, 8, 10, so the next step adds 12.
Where the items come from
The sixteen items are the ICAR's own sample test, public domain and published by Condon and Revelle (2014) in Intelligence, 43, 52 to 64. The answer key is the published key from the R package psychTools, checked against the response data of 1,525 people and against a second, independent adaptation of the same bank that agrees on every key. The difficulty shown beside each item in the review is measured from that response data, not copied from anywhere.
Questions people ask
Is it really free?
Yes. There is no paywall, no email gate and no account needed to see your own result.
Do you keep my answers?
They are stored in your browser on your device, so you can resume a run. Nothing is sent unless you choose to keep an account, and the privacy page states what a group can and cannot see.
How long does it take?
About eight minutes. Most people finish in six to ten.
Can I retake it?
You can, but a second run on the same sixteen items measures your memory of them as much as your reasoning, so treat the first score as the honest one.
Why sixteen items and not a hundred?
Because a short test people finish beats a long one they abandon. The cost is precision: a sixteen-item score has a wider margin than a full battery, and the results page says so rather than hiding it.