There is a ceiling on how much information a person can hold in working memory at once. George Miller's 1956 paper "The Magical Number Seven, Plus or Minus Two" established that short-term memory can hold approximately five to nine items at one time, and this constraint has been a touchstone of cognitive psychology and UX design ever since. Miller's original paper was actually about the limits of our ability to discriminate along a single dimension, not just memory capacity, but the practical implication for designers is clear: do not ask users to hold more than roughly seven items in mind simultaneously.
Miller's Law
Working within the real limits of human short-term memory
A
Designers Academy
10 September 2025 · 5 min read
UXPrinciples
In brief
Miller's Law states that human short-term memory can effectively hold approximately five to nine items, or 'chunks' of information, at once, a principle crucial for designing user interfaces that respect cognitive limits.
