Three short tests, about a minute each: how many numbers you can hold, how many squares you can repeat in order, and how much a clashing word slows you down. Save the scores and take them again in four weeks — nothing leaves this browser.
Your scores
– Take any test and its score appears here.
- Numbers
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- Squares
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- Colours
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Your saved runs (this browser only)
These are screen tests adapted from research tasks, not clinical ones, and they do not diagnose anything — not memory loss, not dementia, not ADHD. This is not medical advice: if your memory or concentration has changed in a way that worries you, that is a conversation with your doctor or pharmacist.
Three short tests you can take in a few minutes: a number memory test (forward digit span), a squares test (visual span) and a Stroop colour test. The average forward digit span for adults is about 6 — 6.35 digits across 763 adults aged 18 to 65 in a published study, with 80% scoring between 5 and 7. Save your scores and take the tests again in four weeks to see whether anything moved.
How to use it
Pick a test and press start. Numbers: digits flash one per second; type them back in order. Squares: squares light up one at a time; tap them in the same order. Colours: a colour word appears in coloured ink; tap the colour of the ink, not the word. Both span tests follow the classic rule — two tries at each length, one right moves you up, two wrong ends it — and your score is the longest length you got right. Add a note if you are trying something (“week 2 of bacopa”), save, and come back.
What each test measures, and what we compare it with
- Forward digit span is short-term verbal memory, one of the oldest measures in psychology. The comparison on this page is Woods et al. (2011): “FS TE-ML scores averaged 6.35 digits” in 763 community adults (mean age 46.5), with “a median span of 6 with 80% of subjects showing spans between 5 and 7 digits”. They heard the digits and said them back; here you see and type them, so read it as a guide, not a ranking.
- Visual span is the same idea for positions instead of numbers, adapted from the Corsi block task. This page prints no published average for it: we could not check a normative table at its source, and an on-screen grid of nine squares is not the wooden board those tables used. Your own first run is the comparison.
- The Stroop test comes from Stroop (1935). Naming the ink colour is slower when the word names a different colour; that delay is the interference, and it is a measure of attention and self-control. Your score is the median time on mismatched words minus the median on matched ones, counting correct answers only.
How the scoring works
| Test | Starts at | Ends | Your score |
|---|---|---|---|
| Numbers | 3 digits | two misses at one length, or 14 digits | longest length right |
| Squares | 3 squares | two misses at one length, or 9 squares | longest length right |
| Colours | 24 words, half matched | after the 24th | mismatched minus matched, in ms |
A colour tap under 100 ms is not counted — nobody has read the ink that fast, the same rule the Reaction Time Test uses — and one over 3 seconds is dropped as a look away.
Worked examples
- Numbers: right at 3, 4, 5 and 6, both 7s missed. Your span is 6 — just under the published 6.35, and inside the 5–7 that 80% of adults scored.
- Numbers: one 8 right on the second try, both 9s missed. Your span is 8: above the average, and above the 5–7 band.
- Colours: matched words took a median 620 ms, mismatched 740 ms. Your interference is +120 ms. Four weeks later it is +95 ms: 25 ms less, which is smaller than a normal day-to-day swing — keep testing before you credit anything.
Common mistakes
- Reading one run as a verdict. Scores rise with practice alone: Woods et al. saw spans grow 0.30 digits over three sessions with nothing else changing. Take it two or three times before you start something, and use the average as your baseline.
- Testing tired and comparing with a fresh day. Same time of day, same device, same amount of coffee — or the comparison says more about your morning than your supplement.
- Reading the word in the colours test. That is the whole point of the test; slow down and name the ink.
- Treating this as a check-up. These are research tasks on a screen. They cannot tell you whether you have a memory problem.
Frequently asked questions
What is the Stroop test?
A colour word printed in a different ink — RED written in blue — and you name the ink. People are slower and make more mistakes when word and ink disagree. That slowdown, the Stroop effect, was first published by J. R. Stroop in 1935 and is still one of the standard tests of attention.
What is a good digit span?
In Woods et al. (2011) adults averaged 6.35 digits forward, and 80% scored between 5 and 7. Seven or more is above that average; four or fewer is below the usual band — and one low run on a tired day means little.
What is the average number memory?
For forward digit span, about 6 digits: 6.35 in the published study used here, 6.6 in the WMS-III sample it compares itself with. Online number memory games that let you keep going usually report higher numbers, because they score differently.
Is this a memory test for dementia?
No. Clinical memory screens are given by a clinician, under set conditions, and interpreted with your history. These are short research tasks on a screen. If you are worried about your memory, see your doctor.
What is a visual memory test?
The squares test here is a visual span test: it measures how long a sequence of positions you can hold and repeat in order. It is adapted from the Corsi block-tapping task, which uses a board of wooden blocks.
Can I use this to see if a supplement works?
You can use it to see whether your scores change — take the tests two or three times first for a baseline, start one thing at a time, and test again at four weeks under the same conditions. Practice alone raises scores a little, so a small gain is not proof.
Read next
- Do nootropics help with memory? — what the trials found, including the ones where nothing did.
- How to train the brain, and why you should
- Three meditation techniques for focus, concentration and memory
- My top three nootropic supplements, each bought and taken for four weeks.
These tests do not diagnose anything and are not medical advice. If your memory or concentration has changed in a way that worries you, talk to your doctor or pharmacist — especially if you take medication such as antidepressants, blood thinners or blood-pressure medicine. Some links on this site are affiliate links: I buy what I review at full price, and a commission never changes a verdict.