Number Memory Test

How to take the number memory test

1. Press Start. A number appears with a shrinking bar under it that shows how long it stays.
2. Memorize it. The display time grows with the level: 2 seconds for short numbers, up to one second per digit later on.
3. When it disappears, type the number and press Submit or Enter. On a phone the numeric keypad opens automatically.
4. If you are right, press Next for a number one digit longer. If you are wrong, the digits you got wrong are underlined in red and your score is the last level you passed.
5. Play again to improve. Your best score is remembered in this browser.

What the results mean

Your score is your digit span: the longest number you repeated correctly. Digit span is one of the oldest measures in psychology and still appears in standard tests of working memory.

Because you have a few seconds to look rather than hearing the digits once, scores here run a little higher than on a spoken digit span test. Compare your rounds against each other rather than against clinical norms.

Why seven? The science of digit span

In 1956 George Miller published "The Magical Number Seven, Plus or Minus Two", observing that people can hold roughly seven items in immediate memory. Later work by Alan Baddeley showed the real limit is about two seconds of speech: you can hold as many digits as you can say to yourself in two seconds, which is why spans are a little longer in languages with short number words. Working memory holds items by rehearsing them, and anything that interrupts the rehearsal (a distraction, a second task) drops items out.

Digit span is part of the Wechsler intelligence scales and many clinical batteries, where forward and backward versions are scored separately. Backward span (repeating the digits in reverse) is harder and taps more of the control part of working memory. This page tests forward span only, and it is a game, not an assessment.

How to remember longer numbers

Chunk the digits into groups of two to four, the way phone numbers are written: 4817 2093 65 is three items, not ten. Say the chunks in a rhythm; rhythm is the cheapest memory aid there is. Look for patterns within chunks: a year, a known number, an ascending run, a repeated digit. Memory athletes go further and convert each pair of digits into a fixed image (a person, an object) and place the images along a familiar route, which is how 100-digit numbers get memorized, but chunking and rhythm alone will add two or three digits to most people's span within a few rounds. For the same skill with positions instead of digits, try the chimp test; for words, the verbal memory test.

Common problems and fixes

The keyboard does not open on my phone

Tap the answer box once. The box uses the numeric keypad; if it still does not open, your browser may block automatic focus, which tapping fixes.

I typed the right number but it says wrong

Look at the red digits in your answer: a swapped pair or an extra digit counts as wrong. Spaces are ignored, so you can type the chunks with spaces if that helps.

The number disappears too fast

The time grows with the length: one second per digit from level 3 onward. If the first level feels short, it is only 2 seconds for one digit, which is plenty once you expect it.

My best score was lost

Best scores live in this browser's storage only. Private browsing and cleared site data reset them.