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Start TestHuman Performance Test
Number Memory Test
A number flashes on screen — memorize it, then type it back. Starts at 3 digits.
- 1.Press Start Test and memorize the number shown.
- 2.Type it exactly into the box and submit.
- 3.Each success adds one digit. One mistake ends the game.
Personal Best: —
The science of digit span
In the 1950s, psychologist George Miller found adults hold about seven (plus or minus two) digits in short-term memory — the famous "magical number seven". Modern research puts the raw limit closer to four chunks, and big scores come from recoding: turning 19475 into "nineteen, four seventy-five" compresses five digits into two meaningful groups. Phone numbers exploit this with their 3-3-4 grouping. This test starts at 3 digits precisely so everyone experiences the comfort zone before the wall, which for most people arrives between digits 7 and 9.
How to remember longer numbers
- Chunk digits into pairs or triples and say each group once, silently.
- Attach meaning: years, ages, prices and postcodes stick better than raw digits.
- Visualise the number written large, left to right, and re-read your mental image.
- Do not rush the memorisation window — calm encoding beats hurried staring.
- Type carefully; most failed runs are typos, not forgotten digits.
FAQ
Number memory FAQ
How does number memory work?
A number appears for a few seconds, then hides. Type it back exactly. Every success adds one digit, starting from 3.
What is a good digit span?
Most adults hold 7±2 digits. Reaching 9–10 digits is strong; beyond that you may be using chunking strategies.
One mistake ends the game?
Yes — a single wrong digit ends the run, and your score is the longest number you correctly recalled.
Why do phone numbers use groups?
Because chunking works: 3-3-4 grouping turns ten digits into three memorable chunks, exactly the strategy that scores highest here.
How long do I see each number?
Viewing time scales with length — roughly an extra 0.7 seconds per digit — so long numbers get proportionally more study time.
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