Key takeaways
Break content into chunks, so that no single group asks for more than a few items.
Seven plus or minus two is not a hard limit for menus or lists: it concerns what must be held in mind at once.
Origins
In 1956 the psychologist George A. Miller published “The Magical Number Seven, Plus or Minus Two”, arguing that the span of immediate memory and the number of items we can tell apart in absolute judgement are both limited to about seven. He also brought in the idea of chunking: grouping information into meaningful units lets us hold more in the same space. Later research suggests that the real limit for new information is lower, around four chunks.
In practice
- Group long numbers, codes and forms into short sections, as with phone and card numbers.
- Show one task at a time instead of loading everything onto one screen.
- Use headings and visual groups, so that people don’t have to hold the structure in their heads.
Further reading
- Miller’s Law, Chunking, and the Capacity of Working Memory — Khan Academy
- Design Principles for Reducing Cognitive Load — Jon Yablonski | Medium.com
- Miller’s Law on Wikipedia — Wikipedia
- Miller’s Law on Laws of UX — Jon Yablonski
The illustration is our own, drawn after the idea of this law’s card in Laws of UX by Jon Yablonski.
