Number Memory

Number Memory is the digit-span working-memory test. A number appears on screen for a few seconds — you have to type it back from memory after it disappears. Each successful level adds another digit. One of the oldest, most-validated psychological tests of short-term memory capacity.

How to play

• Click Start. A 1-digit number appears.
• Shown for 1 + (digits × 0.2) seconds. Progress bar shows time.
• Once it disappears, type the number.
• Press Enter. Correct = advance one digit. Wrong = game over.
• Your best level is saved.

The “magical number 7”

In 1956 George Miller published “The Magical Number Seven, Plus or Minus Two” — one of the most-cited papers in psychology. He showed the average human holds 7±2 items in working memory. This game is essentially Miller’s test. Most people max out between 6 and 9 digits without technique.

Chunking — how to score higher

• Group digits. “147239581” = 9 items. “147-239-581” = 3 chunks.
• Phone-number rhythm. 3-3-3 chunking pattern internalized.
• Pattern look-out. “1234” = one item. “8675309” = Jenny’s number.
• Convert to meaning. “2026” = this year. Pre-existing associations don’t consume slots.
• Articulate aloud. Phonological loop is strong for digits.

Memory champions

World record for digit-span (unlimited rehearsal) exceeds 100 digits using major-system or PAO mnemonic techniques. Raw working-memory ceiling without technique is ~9 digits — past 9 you’re using techniques knowingly or not.

FAQ

• Q: Best beginner strategy? A: Chunk in 3s. Read aloud (or sub-vocally).
• Q: What’s average? A: 7±2 without chunking. With chunking: 10-15. With memory techniques: 50+.
• Q: How long is the display? A: 1 sec + 0.2 sec per digit.
• Q: Can I retry? A: Yes — wrong answer ends round; restart anytime.

For other memory games, try Visual Memory, Simon, Chimp Test, or Sequence Memory.