Laws of UX by Jon Yablonski Summary

Laws of UX explains how psychological principles like Hick’s Law and the von Restorff Effect shape user behavior, offering designers a framework to build intuitive digital experiences. It distills academic research into 21 practical laws, organized into heuristic guidelines, cognitive biases, perceptual principles, and ethical considerations.

UX/UI designers, product managers, and developers seeking to align interfaces with human cognition will benefit most. It’s also valuable for students learning design psychology or professionals aiming to justify design decisions using behavioral science.

Yes—the book remains a cornerstone for human-centered design, with timeless principles applicable to emerging technologies like AI interfaces and AR/VR. Its focus on cognitive psychology ensures relevance despite evolving design trends.

The 190-page book divides 21 laws into four categories: Heuristic Laws (e.g., Jakob’s Law), Gestalt Principles (e.g., similarity), Cognitive Biases (e.g., peak-end rule), and Design Ethics (e.g., Tesler’s Law). Each chapter defines a law, provides examples (e.g., e-commerce layouts), and offers application tips.

• Jakob’s Law: Users prefer familiar interfaces, so follow established patterns.
• Hick’s Law: Decision time increases with options—simplify choices.
• Aesthetic-Usability Effect: Visually appealing designs are perceived as easier to use.

It explores biases like the peak-end rule (users recall peak and final experiences) and Miller’s Law (working memory limits), showing how to structure content into digestible chunks and prioritize impactful interactions.

Tesler’s Law states that every system has inherent complexity designers cannot eliminate. The book advises balancing simplicity by offloading complexity to the system (e.g., automating form fields) rather than the user.

Chapter 11, “With Power Comes Responsibility,” emphasizes ethical considerations like avoiding dark patterns and ensuring accessibility. Yablonski argues that understanding psychology obligates designers to prioritize user well-being.

While both focus on usability, Laws of UX delves deeper into psychology-driven frameworks, whereas Steve Krug’s classic emphasizes heuristic evaluations. They’re complementary—Krug’s book offers methods, Yablonski’s explains underlying principles.

Some note the laws oversimplify complex behaviors or lack original research. However, most praise the book for making academic concepts accessible and actionable for practitioners.

Yes. For example, applying Fitts’s Law (target size/distance) improves button placement, and Postel’s Law (robustness) ensures apps handle input errors gracefully.

As AI interfaces grow, understanding cognitive biases like the Doherty Threshold (system responsiveness) ensures seamless human-AI interactions. The book’s focus on mental models aids in designing intuitive AI tools.