Number Memory Test
The classic digit span task: a number flashes, you type it back from memory, and every correct answer makes the next one a digit longer.
Free in your browser — no download, no sign up. Scores stay on your device.
How it works
- A number appears on screen briefly — display time grows as the number does — and then it disappears.
- Type the number back from memory. Every digit, in order. There is no partial credit.
- You start at 4 digits. Each correct answer adds one digit; the test ends the first time you miss.
- Your score is the longest number you correctly recalled. Your best stays in your browser's local storage — no account, nothing sent to a server.
What is a good number memory score?
The famous benchmark comes from George Miller's 1956 paper in Psychological Review, 'The Magical Number Seven, Plus or Minus Two': immediate memory for digits holds about seven items, give or take. Later work tightened the picture — Nelson Cowan's 2001 review in Behavioral and Brain Sciences argued that once rehearsal and grouping tricks are stripped away, the underlying limit is closer to four chunks. Both numbers come from controlled laboratory conditions — in the classic digit span version, an examiner reads digits aloud at one per second and you repeat them back.
This test is looser than the lab version: the number sits on screen while you read it and nothing stops you from grouping it while you can still see it, so scores here tend to run past a strict auditory span and do not compare directly to the research figures. And we have not run a norming study on our players and we are not going to invent one — a 9 means you correctly recalled a nine-digit number today, and that is all it means.
The digit span task, briefly
Digit span is one of the oldest measures in psychology: it has appeared in memory and intelligence batteries for over a century, usually in two directions — forward, where you repeat the digits as given, and backward, where you repeat them reversed. This page is a forward span, presented visually and typed back, which keeps it honest to the core task: hold an arbitrary sequence briefly and reproduce it exactly.
The single most useful thing to know about the task is chunking. 149217761945 is hopeless as twelve digits and easy as three famous years. Working memory does not hold digits, it holds chunks — and how much a chunk contains is up to you. This is not a cheat; it is the finding. Miller's paper is largely about it.
Can you get better at number memory?
At this test, dramatically — with a catch. In a study by Ericsson, Chase, and Faloon published in Science in 1980, an undergraduate distance runner practiced digit span for over 230 hours and pushed his span from 7 digits to 79, mostly by recoding groups of digits as running times. His memory had not grown; his chunks had.
The catch: tested on letters instead of digits, his span was still an ordinary six or seven. The skill did not transfer, and yours will not either — practicing this test makes you better at this test, not at remembering names or where you parked. We make no claims about training your brain, because the evidence says the training stays remarkably close to home.
FAQ
What is a good score on the number memory test?
By the classic research yardstick, an ordinary digit span is about seven, plus or minus two — that figure is from George Miller's 1956 paper, and Nelson Cowan's 2001 review put the stripped-down limit nearer four chunks. This version is friendlier than the lab task, since the number stays on screen while you read it before it disappears, so scores here run higher and do not map onto those figures. We have not normed this against a population and will not pretend otherwise: your score is the longest number you recalled today, which you can try to beat tomorrow.
What is the magical number seven?
It is the title claim of one of psychology's most cited papers: George Miller's 'The Magical Number Seven, Plus or Minus Two' (Psychological Review, 1956), which observed that immediate memory tends to hold about seven items across many kinds of material. Miller was partly joking about being persecuted by the number; the durable part of the paper is chunking — the observation that the unit memory holds is not the digit but the chunk, and chunks can be grown.
Is this the same digit span test psychologists use?
No. The clinical digit span is administered by a person who reads digits aloud at one per second, runs forward and backward versions, and scores them under standardized rules as part of a larger battery. This is a browser game built on the same core task, under looser conditions. It cannot assess memory problems — if something about your memory worries you, that is a conversation for a clinician, not a burger website.
How can I improve my number memory?
Chunking, immediately: read 4 9 1 7 2 6 as 49-17-26 and you are holding three items instead of six. Grouping in twos and threes is most of the trade. Beyond that, gains come from practice and are narrow — the famous Ericsson study trained one student to a span of 79 digits, and his letter span stayed ordinary. We promise nothing.
Why does the number stay on screen longer when it gets longer?
Display time grows with the length of the number, so a long number still gets time to be read, not just glimpsed. The thing being tested is how much you can hold, not how fast you can read — a fixed flash would quietly turn this into a speed-reading test once the numbers get long.
Does the number memory test measure IQ?
No. Digit span does appear inside professionally administered intelligence batteries, but there it is one subtest among many, given under controlled conditions and interpreted by someone trained to do so. A number you typed into a browser game is not an IQ score, and we will not dress it up as one.
Is the number memory test free?
Yes. Free in your browser, no download, no sign up, no account, and your best score stays in your browser's local storage. The same goes for the other tests on this site — the reaction time test, the CPS test, the typing test, and the Attention Span Test — so you can work through the whole shelf without creating anything.
The Reflex Lab
The Reflex Lab — nine instruments that measure you. Scores stay in your browser.
- Reaction Time Test — median of 5, in ms
- CPS Test — clicks per second
- Spacebar Counter — presses, counted
- Aim Trainer — 30 targets, timed
- Typing Test — words per minute
- Number Memory Test — digits before you break (this page)
- Visual Memory Test — tiles, from memory
- Sequence Memory Test — one step longer each time
- Chimp Test — you, versus Ayumu
For the longer version of being measured, take the two-minute attention span test — scored out of 100.