Number Memory
Remember a number that grows one digit each round.
How to play
- A number appears for a few seconds — memorize it.
- When it disappears, type it from memory.
- Each correct answer adds one more digit.
- One mistake ends the run — your score is the longest number recalled.
What it trains
- Expands working memory span
- Trains focus and mental rehearsal strategies
- Track progress with a clear digit-span score
How many digits can you hold in your head? Memorize the number, type it back, and watch it grow longer every round. A classic working-memory challenge.
The science behind it
Peer-reviewed studies this exercise draws on.
- The magical number seven, plus or minus two: Some limits on our capacity for processing information Miller (1956). Psychological Review, 63(2), 81–97.
- The magical number 4 in short-term memory: A reconsideration of mental storage capacity Cowan (2001). Behavioral and Brain Sciences, 24(1), 87–114.
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