Design Principles

This is a collection of Design principles from around the web. The list was started from a list compiled by Jeremy Keith, a web developer in Brighton, England to whom we are grateful. Copied here because we are interested in expanding it and dreadfully afraid it might disappear one day.

The Robustness Principle

Be conservative in what you send; be liberal in what you accept.

The Pareto Principle

80% of the effects come from 20% of the causes.

The Principle of Least Surprise

When two elements of an interface conflict, or are ambiguous, the behaviour should be that which will least surprise the user.

The DRY Principle

Every piece of knowledge must have a single, unambiguous, authoritative representation within a system.

Personal Design Principles

Tim Berners-Lee

Architectural and philosophical points

These statements of architectural principle explain the thinking behind the specifications. These are personal notes by Tim Berners-Lee: they are not endorsed by W3C. They are aimed at the technical community, to explain reasons, provide a framework to provide consistency for for future developments, and avoid repetition of discussions once resolved.

Principles of Design

  1. Simplicity
  2. Modular Design
  3. Being part of a Modular Design
  4. Tolerance
  5. Decentralization
  6. Test of Independent Invention
  7. Principle of Least Power

Bert Bos

What is a good standard?

Why doesn't HTML include tags for style? Why can't you put text inside SMIL? Why doesn't CSS include commands to transform a document? Why, in short, does W3C modularize its specification and why in this particular way? This essay tries to make explicit what the developers in the various W3C working groups mean when they invoke words like efficiency, maintainability, accessibility, extensibility, learnability, simplicity, longevity, and other long words ending in -y.

An essay on W3C's design principles

  1. Maintainability
  2. Modularity
  3. Minimum redundancy
  4. Accessibility
  5. Device-independency
  6. Internationality
  7. Extensibility
  8. Learnability
  9. Readability
  10. Efficiency
  11. Binary or text format
  12. Implementability
  13. Simplicity
  14. Longevity
  15. Backwards compatibility
  16. Interoperability
  17. Repurposing of content
  18. Timeliness
  19. Use what is there
  20. Design by committee
  21. Expertise
  22. Brevity
  23. Stability
  24. Robustness

Dieter Rams

Ten principles for good design

  1. Good design is innovative
  2. Good design makes a product useful
  3. Good design is aesthetic
  4. Good design makes a product understandable
  5. Good design is unobtrusive
  6. Good design is honest
  7. Good design is long-lasting
  8. Good design is thorough down to the last detail
  9. Good design is environmentally friendly
  10. Good design is as little design as possible

Evan Williams

Ten rules for web startups

  1. Be narrow
  2. Be different
  3. Be casual
  4. Be picky
  5. Be user-centric
  6. Be self-centered
  7. Be greedy
  8. Be tiny
  9. Be agile
  10. Be balanced
  11. (bonus!) Be wary

Bruce Tognazzini

First Principles of Interaction Design

The following principles are fundamental to the design and implementation of effective interfaces, whether for traditional GUI environments or the web. Of late, many web applications have reflected a lack of understanding of many of these principles of interaction design, to their great detriment. Because an application or service appears on the web, the principles do not change. If anything, applying these principles become even more important.
  1. Anticipation
  2. Autonomy
  3. Color Blindness
  4. Consistency
  5. Defaults
  6. Efficiency of the User
  7. Explorable Interfaces
  8. Fitts’ Law
  9. Human Interface Objects
  10. Latency Reduction
  11. Learnability
  12. Metaphors
  13. Protect Users’ Work
  14. Readability
  15. Track State
  16. Visible Navigation

Joshua Porter

Principles of User Interface Design

Interfaces exist to enable interaction between humans and our world. They can help clarify, illuminate, enable, show relationships, bring us together, pull us apart, manage our expectations, and give us access to services. The act of designing interfaces is not art and they are not monuments unto themselves. Interfaces do a job and their effectiveness can be measured. They are not just utilitarian, however. The best interfaces can inspire, evoke, mystify, and intensify our relationship with the world.
  1. Interfaces exist to enable interaction
  2. Clarity is job #1
  3. Conserve attention at all costs
  4. Keep users in control
  5. Direct manipulation is best
  6. One primary action per screen
  7. Keep secondary actions secondary
  8. Provide a natural next step
  9. Appearance follows behavior (aka form follows function)
  10. Consistency matters
  11. Strong visual hierarchies work best
  12. Smart organization reduces cognitive load
  13. Highlight, don't determine, with color
  14. Progressive disclosure
  15. Help people inline
  16. A crucial moment: the zero state
  17. Existing problems are most valuable
  18. Great design is invisible
  19. Build on other design disciplines
  20. Interfaces exist to be used

Sandi Wassmer

The Ten Principles of Inclusive Web Design

Inclusive Design is where innovation and imagination flourish. Meeting the needs of the widest variety of people does not inhibit creativity. It opens our minds and inspires excellence.
  1. Equitable: Be welcoming.
  2. Flexible: Provide options.
  3. Straightforward: Be obvious and not ambiguous.
  4. Perceptible: Don’t assume anything.
  5. Informative: Be timely, predictable, uncomplicated and precise.
  6. Preventative: Provide easy to follow instructions and gently guide users.
  7. Tolerant: Handle errors respectfully.
  8. Effortless: Don’t make demands or place restrictions on your users.
  9. Accommodating: Be approachable, uncluttered and give people room to manoeuvre.
  10. Consistent: Follow standards, guidelines, conventions and best practices.

Organisation­al Design Principles

Principles for Independent Archives

Reduce the cost of using and acting on the evidence in the archive.
Engage new people in the records.
Preserve access to the evidence for as long as possible in as many ways as possible.
  1. Use open standards
  2. Think long term
  3. Stay small, let others create meta-collections
  4. Strive for universal accessibility, be accessible by default
  5. Store the original record, present its essense over its resolution
  6. Work together
  7. Be wary of other people’s ideas


Google’s mission is to organize the world’s information and make it universally accessible and useful.

Ten things we know to be true

  1. Focus on the user and all else will follow.
  2. It’s best to do one thing really, really well.
  3. Fast is better than slow.
  4. Democracy on the web works.
  5. You don’t need to be at your desk to need an answer.
  6. You can make money without doing evil.
  7. There’s always more information out there.
  8. The need for information crosses all borders.
  9. You can be serious without a suit.
  10. Great just isn’t good enough.

Ten principles that contribute to a Googley user experience

  1. Focus on people their lives, their work, their dreams.
  2. Every millisecond counts.
  3. Simplicity is powerful.
  4. Engage beginners and attract experts.
  5. Dare to innovate.
  6. Design for the world.
  7. Plan for today’s and tomorrow’s business.
  8. Delight the eye without distracting the mind.
  9. Be worthy of people’s trust.
  10. Add a human touch.

Government Digital Service

These guidelines are intended for people building digital services for the GOV.UK domain. … We believe that the work should do the talking, so underneath each of the principles there are examples of how we have applied that thinking in the work released so far.

Design Principles

  1. Start with needs
  2. Do less
  3. Design with data
  4. Do the hard work to make it simple
  5. Iterate. Then iterate again.
  6. Build for inclusion
  7. Understand context
  8. Build digital services, not websites
  9. Be consistent, not uniform
  10. Make things open: it makes things better

U.S. Digital Services

To increase the success rate of these projects, the U.S. Government needs a new approach. We created a playbook of 13 key “plays” drawn from successful best practices from the private sector and government that, if followed together, will help government build effective digital services.


  1. Understand what people need
  2. Address the whole experience, from start to finish
  3. Make it simple and intuitive
  4. Build the service using agile and iterative practices
  5. Structure budgets and contracts to support delivery
  6. Assign one leader and hold that person accountable
  7. Bring in experienced teams
  8. Choose a modern technology stack
  9. Deploy in a flexible hosting environment
  10. Automate testing and deployments
  11. Manage security and privacy through reusable processes
  12. Use data to drive decisions
  13. Default to open


Opower Product Design Principles

  1. Design for how people actually behave
  2. Assume people don’t care
  3. Always lead to action
  4. Aim for lasting relationships, not one-night stands
  5. Build for everyone… who receives a utility bill

Indie Web Camp

Key Principles

  • Own your data.
  • Use visible data for humans first, machines second.
  • Build tools for yourself, not for all of your friends.
  • Eat your own dogfood.
  • Document your stuff.
  • Open source your stuff!
  • UX and design is more important than protocols.
  • Build platform agnostic platforms.
  • Build for the long web.
  • Have fun.

Format Design Principles


HTML5 defines the fifth major revision of the core language of the World Wide Web, HTML.

HTML Design Principles

  1. Compatibility

    1. Support existing content
    2. Degrade gracefully
    3. Do not reinvent the wheel
    4. Pave the cowpaths
    5. Evolution not revolution
  2. Utility

    1. Solve real problems
    2. Priority of constituencies
    3. Secure by design
    4. Separation of concerns
    5. DOM consistency
  3. Interoperability

    1. Well-defined behavior
    2. Avoid needless complexity
    3. Handle errors
  4. Universal access

    1. Media independence
    2. Support world languages
    3. Accessibility


A set of simple, open data formats built upon existing and widely adopted standards.

Microformats principles

  1. Solve a specific problem
  2. Start as simple as possible
  3. Design for humans first, machines second
  4. Reuse building blocks from widely adopted standards
  5. Modularity / embeddability
  6. Enable and encourage decentralized and distributed development, content, services

WCAG 2.0

Understanding the Four Principles of Accessibility

The guidelines and Success Criteria are organized around the following four principles, which lay the foundation necessary for anyone to access and use Web content. Anyone who wants to use the Web must have content that is:

PerceivableIt can't be invisible to all of their senses.OperableThe interface cannot require interaction that a user cannot perform.UnderstandableThe content or operation cannot be beyond their understanding.RobustAs technologies and user agents evolve, the content should remain accessible.

Software Design Principles


I want to introduce 7 actionable principles for websites that want to make use of JavaScript to control their UI.

7 Principles of Rich Web Applications

  1. Server rendered pages are not optional
  2. Act immediately on user input
  3. React to data changes
  4. Control the data exchange with the server
  5. Don’t break history, enhance it
  6. Push code updates
  7. Predict behavior


An open source content management platform

Drupal 7 User Experience Project

  1. Make the most frequent tasks easy and less frequent tasks achievable.
  2. Design for the 80%
  3. Privilege the Content Creator
  4. Make the default settings smart


Instead of reviewing restaurants, you can recommend your favorite dishes and see what others have recommended wherever you go.

About Foodspotting

  1. It’s about dishes, not just restaurants
  2. It’s visual
  3. It’s positive
  4. It’s global


It's what enables us to debate whether something “Is Facebook” or “Isn't Facebook,” it's what allows us to evaluate whether anything we’re designing could be improved.

Facebook Design Principles

  1. Universal
  2. Human
  3. Clean
  4. Consistent
  5. Useful
  6. Fast
  7. Transparent


After a few weeks sketching and debating, we stepped back and created some simple design principles before moving forward:

Our principles

  • Interaction is the basic unit of design.
  • Transitional interfaces are easier to learn and more pleasant to use.
  • Interactions should be delightful and surprising.
  • Focus the user on one primary action at a time.


Is what we’re making a clear expression of what it means to be Firefox? What will make it more Firefoxy? What will we not do because it’s not true to Firefox?

Firefox Design Values

  1. Takes care of you

    • user-sovereignty
    • default to privacy
    • no surprises
    • actionable advice
  2. You help make it

    • research gives a voice to our non-core community
    • start people with smart defaults
    • implicit as well as explicit customization
    • invite people to be more than users
  3. Plays well with others

    • user control and choice
    • simple to use the services you choose
    • suggest ways to get the most out of the web
  4. Exuberant

    • feels like there is a person at the other end
    • fun tools are easier to use
    • humour and whimsy
    • have a point of view
  5. Finely crafted

    • see also our visual design guidelines
    • continuity of look and feel across platforms
    • perceivable quality is vital
  6. Global

    • global means local and local and local
  7. Balances power and simplicity

    • 80/20/2: default to surface minimalism and easy access to the rest
    • user-agency and understanding, not just less
  8. Makes sense of the web

    • focus on real human tasks and contexts
    • many real tasks involve a browser and other tools
    • quick access to your stuff and web
    • no jargon
  9. High user-performance

    • performance is objective, but responsiveness is subjective
    • a happy user performs better


Windows UX Design Principles

  • Reduce concepts to increase confidence
  • Small things matter, good and bad
  • Be great at “look” and “do”
  • Solve distractions, not discoverability
  • UX before knobs and questions
  • Personalization, not customization
  • Value the life cycle of the experience
  • Time matters, so build for people on the go

Windows Apps

Microsoft design principles

  • Pride in craftsmanship
  • Do more with less
  • Fast and fluid
  • Authentically digital
  • Win as one


These design principles were developed by and for the Android User Experience Team to keep users' best interests in mind. For Android developers and designers, they continue to underlie the more detailed design guidelines for different types of devices.

Android Design Principles

  • Enchant Me

    • Delight me in surprising ways
    • Real objects are more fun than buttons and menus
    • Let me make it mine
    • Get to know me
  • Simplify My Life

    • Keep it brief
    • Pictures are faster than words
    • Decide for me but let me have the final say
    • Only show what I need when I need it
    • I should always know where I am
    • Never lose my stuff
    • If it looks the same, it should act the same
    • Only interrupt me if it's important
  • Make Me Amazing

    • Give me tricks that work everywhere
    • It’s not my fault
    • Sprinkle encouragement
    • Do the heavy lifting for me
    • Make important things fast

Android Wear

These design principles provide some simple heuristics about how you should plan and assess your Android Wear app design.

Design Principles for Android Wear

  • Focus on not stopping the user and all else will follow
  • Design for big gestures
  • Think about stream cards first
  • Do one thing, really fast
  • Design for the corner of the eye
  • Don’t be a constant shoulder tapper

Google Glass

Glass is fundamentally different than existing mobile platforms in both design and use. Follow these principles when building Glassware to give users the best experience.


  • Design for Glass
  • Don’t get in the way
  • Keep it relevant
  • Avoid the Unexpected
  • Build for people

Harmony by Intuit

Our vision is to create a cohesive, multi-device user experience that unites Intuit’s small business products.

Design Principles

  • Be simple, easy to use, and guiding.

    1. Establish a familial resemblance.
    2. Maintain user context by staying in place.
    3. Guide the user where appropriate.
  • Design for the customer and instill confidence.

    1. Be trustworthy and helpful.
    2. Imbue confidence.
  • Establish modern and iconic ownable moments.

    1. Define a standard personality.
    2. Celebrate unique tasks.
    3. Project a voice.
    4. Define ownable visualizations.
  • Celebrate data while respecting user and device context.

    1. Be smart and appropriate for the task at hand.
    2. Understand the broader contexts of use.

Hardware Design Principles

The Clock Of The Long Now

These are the principles that Danny Hillis used in the initial stages of designing a 10,000 Year Clock. We have found these are generally good principles for designing anything to last a long time.


LongevityWith occasional maintenance, the clock should reasonably be expected to display the correct time for the next 10,000 years.MaintainabilityThe clock should be maintainable with bronze-age technology.TransparencyIt should be possible to determine operational principles of the clock by close inspection.EvolvabilityIt should be possible to improve the clock with time.ScalabilityIt should be possible to build working models of the clock from table-top to monumental size using the same design.


Guide for Designers

  1. Rather than solving problems from scratch, adapt other people's solutions, and then give them credit.
  2. Design for materials and components which are reasonably cheap to buy, low-carbon and fully recyclable or biodegradable.
  3. Design structures which can be assembled with minimal formal skill or training, and without the use of power tools.
  4. WikiHouses should be capable of being habitable throughout the year, and as efficient as possible in the use of energy and water.
  5. Design in such a way as to offer maximum provision for the safety, security and health (both mental and physical) of the users at all stages of the structure's life.
  6. As a general rule, design for the climate, culture, economy and legal / planning framework in which you live, and you know best. Others will then be able to adapt the design to suit their environment.
  7. Share your work as much and as openly as possible, it might come back better. At very least you'll have contributed to solving a common problem.
  8. “It is easier to ship recipes than cakes and biscuits” — John Maynard Keynes
  9. Design to dismantle. The easier it is to dismantle structures or replace individual parts, the better.
  10. Design for mistakes. Try to design components which either make it impossible for the assembler to get it wrong or are designed in such a way that it doesn't matter if they do.