How the test works
Choose one or three lives and press Start. The screen goes dark and a number appears with a bar underneath that runs down while the number is visible. The time grows with the length: one second to read plus half a second for every digit, so a seven-digit number stays for four and a half seconds. Then the number disappears and a keypad takes its place. Type the digits with the keypad or with the number keys on your keyboard, correct a slip with the ⌫ key on the keypad or Backspace, and confirm with OK or Enter.
- A right answer shows the number again and the next one has one more digit.
- A wrong answer shows the number and your answer one above the other, with the digits you missed underlined. With lives left you get a new number of the same length; without, the run ends.
- A hidden tab while the number is on screen does not cost a life. You simply get a new number of the same length, because a number you could not see tests nothing.
At the end, See result closes the screen and the result card shows the longest number you recalled and your record for that lives option on this device. Esc or the × button leaves earlier without a result, because a run you stopped yourself does not say where your memory runs out.
What the result means
The test measures your forward digit span: how many digits you can hold in short-term memory for a few seconds and repeat in order. It is one of the oldest measures in psychology and a standard part of memory and intelligence tests, because it is simple and very stable for a given person.
- Five or fewer. Below the usual range. Tiredness, distraction or a first try are the common reasons; take it again when you are rested.
- Six to eight. The normal range for adults.
- Nine to eleven. Above average. Many people reach this with a few rounds of practice and a steady rhythm.
- Twelve or more. You are almost certainly using a technique, consciously or not, such as grouping digits into dates, prices or phone numbers.
A single run is noisy: one unlucky number with two similar digits next to each other can cost you a level. Three runs, or the three-lives option, give a steadier picture. Digit span changes little from day to day, but sleep, stress and alcohol all lower it, and it slowly declines with age.
How to get a better score
Short-term memory is limited, but how you use it is not. Say the digits to yourself in groups of two or three instead of one by one: 48 15 16 23 is four items, 4 8 1 5 1 6 2 3 is eight. Give the groups a meaning if one jumps out, such as a year, a time of day or the start of a phone number. Keep your eyes on the number for its whole time instead of glancing down at your keyboard early, and type immediately while the sound of the digits is still fresh. Quiet surroundings help more than you would expect: a conversation in the background competes for the same inner voice you use to rehearse.
When to take a low result seriously
This is a quick self-test for curiosity and practice, not a medical assessment. A low score on one evening says more about the evening than about your memory. If you or someone close to you notice lasting memory problems in daily life, such as forgetting recent conversations, getting lost on familiar routes or repeating the same questions, talk to a doctor. A proper assessment looks at much more than a digit span and can find causes that are often treatable, from poor sleep and vitamin deficiency to side effects of medication.
Frequently asked questions
How many digits can an average person remember?
Most adults hold six to eight digits in a test like this, seven on average. The figure was made famous by George Miller's 1956 paper on the magical number seven, plus or minus two. Reaching nine or ten is good, and results above twelve almost always come from a deliberate technique such as grouping the digits or turning them into pictures.
Why does the test start with one digit?
So that every length on the result card was really tested. If the test began at seven digits, someone who missed the first number would get six, a length they were never asked for. The short numbers take only a few seconds, and they also let you settle into the rhythm before it gets hard.
What does the lives option change?
With one life, the first mistake ends the run, as in the classic version of the test. With three lives, a mistake gives you a new number of the same length instead, and the run ends on the third mistake. Three lives measure what you can usually do rather than what you do on your worst attempt, so the result tends to be a digit or so higher. Records are kept separately for each option.
Is it cheating to repeat the number out loud?
No, repeating the digits under your breath is exactly how short-term memory for numbers normally works, and most people do it without noticing. Writing the number down or taking a screenshot is a different matter: that measures your phone, not your memory, and the result is only meaningful if you do not.
Is my score saved or sent anywhere?
Only your best length for each lives option is kept, in your browser's local storage on this device. The numbers, your answers and your results never leave the device and there is no leaderboard. Clearing site data removes the record; a private window starts without it and forgets its own record when closed.