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Miller's 7 ± 2

STR·03 · 3 of 11

Immediate memory holds about seven chunks — said Miller, about a specific laboratory task, once.

folk Widely repeated, and the evidence does not support it as it is used. Why: Miller published a real result about a specific task, then protested the generalisation himself. "Seven items in a menu" is not what the paper says.

The same task, built twice

Both panes below are real interfaces. They respond, they can be got wrong, and each is timed from your first move in it. The times are not a study — two panes, one reader, no controls. They are here to make a difference you can feel into a number you can see, and nothing is recorded or sent anywhere.

Your task

Press Show, read the reference, then type it back from memory.

Unchunked—

Eleven digits as one run. Miller's number is about how many chunks working memory holds, and an unchunked string of eleven is eleven chunks.

Chunked—

The same eleven digits in groups of three and four. Nothing was removed and nothing was simplified — the load fell because the grouping did the chunking for you.

What to watch This is the half of Miller that replicates, and it is not the half people cite. The paper is about chunking; it says nothing about how many items belong in a navigation menu. This bench demonstrates the real finding and refuses the folk one.

The principle

OriginGeorge Miller, "The Magical Number Seven, Plus or Minus Two" (1956) — a review of short-term memory span; the paper's real gift is chunking.
EvidenceChunking is robust and genuinely useful: phone-number grouping, IBAN spacing, code formatting. Later work (Cowan, 2001) puts the practical span nearer four.
Limits & misuseThe card exists for this field. "Menus must have seven items" appears nowhere in Miller — a navigation menu is on screen, and recognition is not recall. Miller himself spent years bemused that a paper about memory span became a law about menu length. The Institute keeps the principle because its misuse is the best available lesson in how citations decay into folklore.