Jakob’s Law
People bring expectations learned from other products, so familiar conventions often reduce the effort needed to begin using a new interface.
Direct explanation
What it means
A product does not teach from zero. Common placement, language, and behavior supply a starting model; innovation is valuable when it earns the cost of teaching a new pattern.
Ignoring established expectations can turn ordinary actions into puzzles, while copying conventions uncritically can preserve harmful or inaccessible patterns.
Research anchor: Jakob Nielsen
Research and interpretation
What the research found
The concept is a practitioner synthesis: users spend most of their time with other products and form expectations from them.
Research on mental models, transfer, and consistency supports the underlying rationale, but Jakob’s Law itself is not a single controlled finding.
Popular advice versus careful use
Common shorthand: Copy whatever the market leader does.
Use familiar interaction language as the default, then depart when evidence supports a clearer, safer, or more capable alternative.
How designers apply it
- 01
Place cart and account access where ecommerce visitors expect them.
- 02
Use standard form labels and browser-compatible input behavior.
- 03
Introduce a novel editor gesture alongside visible conventional controls.
Original UI examples
responsive ecommerce
Travel checkout
Dates, travelers, price summary, and payment follow familiar booking language.
Travelers can focus on policy differences instead of relearning the transaction structure.
desktop creative tool
Spatial music editor
A new two-dimensional gesture also has labeled sliders, undo, and a short contextual demonstration.
The distinctive control is learnable because conventional alternatives remain.
Deleting a saved item
Less effective
Replace the familiar trash action with an unexplained swipe-only gesture.
Better fit
Offer an explicit accessible delete control and teach the optional gesture in context.
A familiar convention still needs clear consequences and recovery.
Limits and failure modes
Conventions differ across cultures, platforms, eras, and user groups, and familiar patterns can still be poor patterns.
Common mistakes
- Treating competitor popularity as proof of usability.
- Refusing all innovation because users already know another pattern.
When it should not dominate
- When the convention is deceptive, exclusionary, or mismatched to the task.
- When research shows a new pattern creates substantial net benefit.
Responsible use
Accessibility
Prefer conventions that work with platform accessibility APIs, keyboard behavior, autofill, zoom, and assistive technologies; familiarity is not evidence of conformance.
On mobile: Respect platform navigation and input expectations while keeping cross-platform meaning consistent.
Ethics and context
Do not copy dark patterns merely because users recognize them, and do not exploit familiar visual forms for misleading ads or consent.
On desktop: Honor browser behaviors, keyboard shortcuts, pointer cues, and resizable layouts.
Designer checklist
- Identify the relevant platform and domain convention.
- State the benefit before deviating.
- Test the transition with newcomers and experienced users.
Check your understanding
Which statement applies Jakob’s Law most carefully?
Practice and continue learning
See ideas in real interfaces
These external interfaces are editorial references, not examples created to demonstrate this principle.
Sources and further reading
- 01Open source
Jakob's Law of Internet User Experience
Jakob Nielsen · Nielsen Norman Group
Authoritative secondary · primary or original source
- 02Open source
Mental Models
Philip N. Johnson-Laird · 1983 · Harvard University Press
Book · primary or original source
Continue the graph
Related principles
model
Mental Models
A mental model is a person’s internal, partial representation of how a system works and what actions will produce.
model
Conceptual Models
A conceptual model is the designed explanation of a system’s objects, relationships, actions, and state that the interface presents to users.
usability heuristic
Recognition Rather Than Recall
Make relevant objects, actions, and options visible or readily retrievable so people do not have to recall them unaided.