Tip: chunk the digits in groups of three, like a phone number — it more than doubles most people's span.
Number Memory — free digit span test in your browser
Number Memory is the classic digit span test turned into a game. A number flashes on screen for a few seconds, then disappears — your job is to type it back from memory. Start with 3 digits; every correct answer adds one more. One mistake and the run is over, with a digit-by-digit breakdown of exactly where your memory slipped.
It's free, runs in any browser with no download, and works one-handed on your phone with the built-in number pad. Rounds take seconds, restarts are instant, and your best span is saved on your device — the perfect "one more try" brain teaser.
How to play
- Memorize the number while the timer bar shrinks — longer numbers get more time.
- When it vanishes, type the digits using the on-screen pad or your keyboard.
- Fix mistakes with ⌫ backspace, then hit OK (or Enter) to submit.
- Correct = level up, one digit longer. Wrong = game over — your score is the longest number you completed.
What your digit span says about working memory
The digit span task is one of the oldest tools in psychology — it has been part of IQ tests for over a century because it directly measures working memory, the mental scratchpad you use to hold information while you think. In 1956, psychologist George Miller famously pegged its capacity at "the magical number seven, plus or minus two": most adults can reliably repeat back 5–9 digits, and scores above 10 are genuinely rare without training.
The trick that beats the limit is chunking: your scratchpad holds about seven items, not seven digits — so make each item bigger. Read 149217762001 as 1492 · 1776 · 2001 and twelve digits collapse into three memorable chunks. Rhythm helps too, which is why phone numbers are printed in groups. Memory athletes push this to hundreds of digits by converting chunks into vivid images — but even simply saying the digits in groups of three, out loud in your head, will move your score noticeably in a few runs.
More games
Test the rest of your brain: try Sequence Memory or the Reflex Test, or browse all games.