What it measures
The power to briefly hold a number in your mind and immediately retrieve it. Psychologists call this working memory. Memorizing a phone number to type it in, or recalling directions seconds after hearing them — that's this power at work.
How many digits can most people hold?
Classic research suggests adults' digit working memory capacity averages 7±2. But that's when silently rehearsing — visual memory for briefly shown numbers tends to be a bit shorter.
| Digits | Approximate |
|---|---|
| 3–4 | Starting level |
| 5–6 | Around average |
| 7–8 | Above average |
| 9–11 | Large capacity |
| 12~ | Rare |
How to hold more
Chunking
Breaking numbers into meaningful groups holds much more. Don't see 821994 as six individual digits — see 82·19·94 as three chunks and your capacity expands.
Repetition
Short, repeated exposure sticks better than one long view. Playing this game once or twice a day can gradually expand your working memory capacity.
Attention
Memory begins with attention. If your mind wanders while the number is shown, that round is almost certainly lost. Practicing focus is memory training.
FAQ
Why numbers?
Numbers are the simplest, most comparable stimulus. Letters and images invite semantic associations that make it hard to measure pure capacity.
Why is the display time so short?
Show it longer and you can rehearse in your head, pushing it into long-term memory. Short display times measure instantaneous holding power more accurately.
One wrong answer and it's over?
Yes. The moment you fail, the digits you reached becomes your score. Restart and you begin at 3 digits.