What is chunking and why does it improve memory?

The short answer

Chunking is the cognitive strategy of grouping individual items into larger, meaningful units — effectively reducing the number of memory items without reducing the amount of information stored. It is why experts can remember far more in their domain than novices.

The data

What it means for you

Chess grandmasters can remember board positions after a 5-second glance not because they have better general memory — in controlled tests, they score average on random digit spans. They have better chunking for board patterns: where a novice sees 32 pieces, a grandmaster sees 4–5 recognisable formations.

On the Number Memory test, chunking is the primary strategy used by high scorers (10+ digits). Try grouping 4-5 digit numbers into familiar patterns (years, phone codes, prices) and retesting to see the improvement firsthand.