About the Digit Span Test
Digit span is the longest string of digits you can repeat back in the correct order after seeing or hearing it once. Joseph Jacobs first measured it systematically with students in 1887, and it remains one of the oldest and simplest tasks for studying working memory.
This site lets you run that task in your browser. Once the digits disappear, you type them back exactly as shown (forward) or in reverse (backward). Each correct answer makes the next string one digit longer until you find the longest span you can hold. Everything runs inside your browser, and your history stays on this device.
This is a measurement for fun and self-checking. It is not an IQ test and not a medical diagnosis.
Features
- Forward digit span: start at 3 digits and type them in the order you saw (or heard) them. A correct answer adds one digit; after a miss you get one more try at the same length, and two misses at the same length end the test.
- Backward digit span: same rules, but you type the digits in reverse, starting with the last one. On top of holding the digits, you have to flip their order.
- Presentation: show the whole string at once (displayed for number of digits × your time setting) or one digit at a time (1-second interval by default). The time per digit can be set from 0.5 to 2 seconds.
- Listening mode: your browser's speech synthesis (Web Speech API) reads the digits aloud one at a time. If your device has no voice for the current language, the mode is turned off and the reason is shown.
- Records: a try-by-try comparison of what was shown and what you typed, personal bests for each direction, a trend chart across tests and your recent results, all kept in this browser's localStorage.
- Sharing: copy your result as a single line, with a link that opens the test with the same settings.
How to use
- In the settings on the right (below on mobile), pick the direction, sense, presentation, seconds per digit and starting length.
- Press Start. A short "get ready" cue appears, then the digits (in listening mode they are spoken). Input is blocked while the digits are being presented.
- When the digits disappear, type them with the on-screen keypad or your keyboard's number keys and press OK (Enter). Use ⌫ or Backspace to delete.
- You'll see whether you were right, with a digit-by-digit comparison. Press Next (Enter) to continue.
- After two misses at the same length, your longest span is shown in large type and the result is saved.
Frequently asked questions
How many digits is normal?
This site does not grade scores or turn them into percentiles. The figure most often quoted is Miller's (1956) "7±2", but that is a summary of many immediate-memory experiments, not a standardized norm. Age norms for standard tests come from fixed procedures and specific samples, so they can't be compared directly with scores from a tool that presents digits differently. Use this test to track your own results over time with the same settings.
My backward score is lower than my forward score.
That's the case for most people. Backward span requires you to hold the digits while reversing their order, which adds a "manipulation" load on working memory. The differences are explained in the forward vs backward guide.
Is this an IQ test?
No. Digit span is used as one subtest in some intelligence tests, but on its own it does not represent intelligence. Results on this site are not a substitute for an IQ test or a medical diagnosis. If you are worried about your memory, talk to a professional.
Listening mode is turned off.
Listening mode uses the voices provided by your browser and operating system. It won't turn on if no voice is installed for the current language or if your browser doesn't support speech synthesis. Add a voice for that language in your system's speech (text-to-speech) settings, then reload the page.
Can I group the digits to remember them?
Yes. Grouping digits into chunks is a strategy almost everyone uses naturally, and it raises scores. Just solve the test in a similar way each time if you want your trend to be meaningful. See the chunking guide.
Where are my results stored?
Only in this browser's storage (localStorage) on this device; nothing is sent to a server. Results don't sync to other devices and are deleted if you clear your browser data or press "Clear history".
Will practice improve my memory?
Your digit span score can rise with practice and strategy. However, several meta-analyses conclude that there is little evidence those gains carry over broadly to other tasks or everyday abilities. The research is summarized in the memory training guide.
My results vary a little every time.
That's normal. The digits are randomly generated each time, and a difference of one or two digits due to focus, tiredness or background noise is common. An average and trend across several tests are more reliable than a single score.
References
- Jacobs, J. (1887). Experiments on "prehension". Mind, 12(45), 75–79.
- Miller, G. A. (1956). The magical number seven, plus or minus two. Psychological Review, 63(2), 81–97.
- Cowan, N. (2001). The magical number 4 in short-term memory. Behavioral and Brain Sciences, 24(1), 87–114.
- Baddeley, A. D., & Hitch, G. (1974). Working memory. Psychology of Learning and Motivation, 8, 47–89.
- Ericsson, K. A., Chase, W. G., & Faloon, S. (1980). Acquisition of a memory skill. Science, 208(4448), 1181–1182.
- Melby-Lervåg, M., & Hulme, C. (2013). Is working memory training effective? A meta-analytic review. Developmental Psychology, 49(2), 270–291.