--- title: "Miller’s Law" url: "https://www.insideuxdesign.com/en/glossar/millers-law" language: "en" description: "What is Miller’s Law? A plain explanation with current research, an example and practical tips. Learn why it doesn’t mean “max. 7 menu items.”" published: "2026-10-14T15:20:04+02:00" updated: "2026-10-14T15:20:04+02:00" --- # Miller’s Law Miller’s Law describes the observation that people can only hold a small number of information units in short-term memory at once. Miller suggested about seven in 1956; newer research points to about four. - **Buchstabe:** M - **Englischer Begriff:** Miller’s Law UX glossary · engl. Miller’s Law # Miller’s Law Miller’s Law describes the observation that people can only hold a small number of information units in short-term memory at once. Miller suggested about seven in 1956; newer research points to about four. Imagine someone reads you a customer number over the phone: “4 8 1 9 2 7 3 0 5 6 2.” You don’t have a pen and try to keep it in your head. By halfway through, you’re struggling. If the person says “481, 927, 305, 62” instead, it’s much easier. That difference is what Miller’s Law is about. ## Explained simply In 1956, psychologist George A. Miller published the paper “The Magical Number Seven, Plus or Minus Two.” In it, he described how people can only keep about seven units in short-term memory (the store for what you’re holding in mind right now), give or take two. What Miller found most interesting was that these units aren’t single letters or digits, but meaningful groups called **chunks**. Seven single letters are about as hard to remember as seven short words, even though the words contain many more letters. An everyday comparison: you remember a date like 14 July 1989 as day, month and year, three chunks rather than a long string of digits. ## What research says today The “seven” is more of a rough rule of thumb than a fixed measure, and Miller himself used “magical” rhetorically. In a widely cited 2001 review, Nelson Cowan concluded that pure capacity is closer to three to five chunks, about four on average. How much actually fits also depends on the material, prior knowledge and the situation. For more on the basics, read [Basics of Human Perception: Short-Term Memory](https://www.insideuxdesign.com/en/blog/basics-of-human-perception-short-term-memory). ## Common misconceptions The best-known misconception goes like this: “A menu can have no more than seven items.” Miller’s work doesn’t support that. The limit applies to things you have to remember without seeing them. A menu, however, is visible on screen. People recognize the right option there instead of recalling it from memory. The Nielsen Norman Group explicitly calls the seven-item rule for menus a misconception. A well-structured menu with ten clear entries can work better than seven abstract umbrella terms. ## An example Here’s an example: a payment form asks for an IBAN (the international bank account number used in Europe) in a single field without spaces. Anyone typing it from an invoice keeps losing their place and ends up checking it digit by digit. After the redesign, the field automatically groups the input into blocks of four, the way it usually appears on invoices and bank statements. The number is the same, but it now breaks down into easy-to-scan chunks. ## In practice - **Break information into chunks.** Numbers, long texts and forms get easier when you split them into meaningful groups, for example with subheadings or spacing. - **Favor recognition over recall.** Show important information where people need it instead of making them remember it across several steps. This reduces [cognitive load](https://www.insideuxdesign.com/en/glossar/cognitive-load). - **Don’t use seven as an excuse.** Decide how many menu items you need based on content and testing, for example with [card sorting](https://www.insideuxdesign.com/en/glossar/card-sorting), not based on a number. You’ll find more principles in the [Laws of UX](https://www.insideuxdesign.com/en/ressourcen/laws-of-ux) resource. ## Related terms [Working Memory](https://www.insideuxdesign.com/en/glossar/working-memory), [Cognitive Load](https://www.insideuxdesign.com/en/glossar/cognitive-load), [Hick’s Law](https://www.insideuxdesign.com/en/glossar/hicks-law), [Progressive Disclosure](https://www.insideuxdesign.com/en/glossar/progressive-disclosure) ## Sources - [Wikipedia: The Magical Number Seven, Plus or Minus Two. Overview of George A. Miller, Psychological Review, 1956](https://en.wikipedia.org/wiki/The_Magical_Number_Seven,_Plus_or_Minus_Two) - [Nelson Cowan: The magical number 4 in short-term memory: A reconsideration of mental storage capacity. Behavioral and Brain Sciences 24 (1), 2001](https://www.cambridge.org/core/journals/behavioral-and-brain-sciences/article/magical-number-4-in-shortterm-memory-a-reconsideration-of-mental-storage-capacity/44023F1147D4A1D44BDC0AD226838496) - [Jakob Nielsen: Short-Term Memory and Web Usability. Nielsen Norman Group, 2009](https://www.nngroup.com/articles/short-term-memory-and-web-usability/) - [Kate Moran: How Chunking Helps Content Processing. Nielsen Norman Group, 2016](https://www.nngroup.com/articles/chunking/) ## More terms [ ### A/B Testing An A/B test is an experiment that shows two versions of a page or element at the same time to randomly split groups of visitors. It lets you decide with real data which version works better. ](https://www.insideuxdesign.com/en/glossar/a-b-testing) [ ### ARIA ARIA is a W3C standard that adds roles, states and properties to HTML. It tells screen readers what an element is and how it currently behaves. ](https://www.insideuxdesign.com/en/glossar/aria) [ ### Accessibility Accessibility means designing websites, apps and digital documents so that everyone can use them, including people with visual, hearing, motor or cognitive disabilities. ](https://www.insideuxdesign.com/en/glossar/accessibility) [ ### Affordance An affordance describes what action an object makes possible and whether people can recognize it: a button invites you to press it, a handle invites you to pull. ](https://www.insideuxdesign.com/en/glossar/affordance) [ ### Alt Text Alt text is a short text version of an image, stored in the HTML alt attribute. Screen readers read it aloud so people who can’t see the image get the same information. ](https://www.insideuxdesign.com/en/glossar/alt-text) [ ### Atomic Design Atomic Design is a method for building user interfaces from small, reusable building blocks, from single elements like buttons all the way up to complete pages. ](https://www.insideuxdesign.com/en/glossar/atomic-design) [ ### BFSG The BFSG, Germany’s Accessibility Strengthening Act, has required many companies since 28 June 2025 to make certain products and digital services, such as online shops, accessible. ](https://www.insideuxdesign.com/en/glossar/bfsg) [ ### Card Sorting Card sorting is a research method in which people sort terms written on cards into groups. It shows you how they mentally organize content, so you can plan navigation that makes sense to them. ](https://www.insideuxdesign.com/en/glossar/card-sorting) [ ### Cognitive Load Cognitive load is the mental effort it takes to understand and use an interface. The less unnecessary thinking a design demands, the easier the actual task becomes. ](https://www.insideuxdesign.com/en/glossar/cognitive-load) [ ### Color Vision Deficiency A color vision deficiency means someone has a harder time telling certain colors apart than most people. The most common type is red-green deficiency. ](https://www.insideuxdesign.com/en/glossar/color-vision-deficiency) [ ### Contextual Inquiry Contextual inquiry is a research method where you observe and interview people in their real work environment. It shows you how they actually get tasks done, not just how they describe it. ](https://www.insideuxdesign.com/en/glossar/contextual-inquiry) [ ### Contrast Ratio The contrast ratio describes how much two colors differ in brightness, such as text and background. WCAG requires at least 4.5:1 for normal text. ](https://www.insideuxdesign.com/en/glossar/contrast-ratio)