Usability Guidelines
Acknowledgments: Gerry Gaffney, Jakob Nielsen, Larry Constantine, Jared Spool
On this page:
Navigation
Functionality
User control
Language, content
Online help, user guides
System, user feedback
Web accessibility
Consistency
Error prevention, correction
Architectural and visual clarity
Usability @ MIT
The guidelines below include most factors to consider during a usability evaluation of a web site. Not all factors apply to every site.
For a much more extensive set of guidelines, we recommend Research-Based Web Design & Usability Guidelines created for the National Cancer Institute. This is an excellent resource for usability practitioners and designers and developers.
View/print selected guidelines (PDF)
Navigation
- Current location within the site is shown clearly
- Link to the site's main page is clearly identified
- Major/important parts of the site are directly accessible from the main page
- Site map is provided for a large, complex site.
- Easy to use Search function is provided, as needed.
Functionality
- Site accommodates novice to expert users.
- Functions are clearly labeled
- Essential functions are available without leaving the site.
- Plug-ins are used only if they add value.
User Control
- Site reflects user's workflow
- User can cancel any operation
- Clear exit point is provided on every page
- Per-page size is less than 50K, to accommodate slow connections
- All appropriate browsers are supported
Language and Content
- Important information and tasks are given prominence
- Information of low relevance or rarely used information is not included
- Related information or tasks are grouped:
- on the same page or menu
- in the same area within a page
- Language is simple, without jargon
- Paragraphs are brief
- Links are concise, expressive, and visible--not buried in text
- Terms are defined
Online Help and User Guides
- Site is designed to require minimal help and instructions
- Help and instructions, if needed, are easily accessible
System and User Feedback
- It is always clear what is happening on the site -- visual hints, etc.
- Users can receive email feedback if necessary
- Users can give feedback via email or a feedback form
- Confirmation screen is provided for form submittal
- All system feedback is timely
- Users are informed if a plug-in or browser version is required
- Each page includes a "last updated" date
Web Accessibility
Tools, checklist, and guidelines at: www.w3.org/TR/WAI-WEBCONTENT
- Site follows current web standards. See HTML 4.0, Cascading Style Sheets (CSS1)
Cascading Style Sheets are used for layout and style where possible - Images and animations . The attribute ALT= is used for images, animations, and other objects
- Image maps . Site uses client-side map and text for hotspots
- Multimedia. Site provides captioning and transcripts of audio; and descriptions of video
- Web versions of PDF documents are provided
- Link labels makes sense when read out of context; site avoids link names such as "click here"
- Page organization is accomplished with headings, lists, and consistent structure
- Graphs and charts. Summaries are provided for graphs and charts, or the LONGDESC attribute is used
- Scripts, applets, & plug-ins. Alternative content is provided for scripts, applets, and plug-ins in case these active features are inaccessible or unsupported
- Frames. For frames pages, site includes the NOFRAMES option and meaningful titles
- Tables. Line-by-line reading of tables is sensible, and summaries are included where possible
- Validation. Site has been validated using the W3C's HTML Validation Service and the Bobby Accessibility Checker
- Site has been tested on a variety of platforms (Windows, Mac, Linux, Unix) and browsers (Netscape 6, 7; IE 5, 6; lynx)
Consistency
- The same word or phrase is used consistently to describe an item
- Link reflects the title of the page to which it refers
- Browser page title is meaningful and reflects main page heading
Error Prevention and Correction
- Users can rely on recognition, not memory, for successful use of the site
- Site tolerates a reasonable variety of user actions
- Site provides concise instructions for user actions, including entry format
- Error messages are visible, not hidden
- Error messages are in plain language
- Error messages describe actions to remedy a problem
- Error messages provide a clear exit point
- Error messages provide contact details for assistance
Architectural and Visual Clarity
- Site is organized from the user's perspective
- Site is easily scannable for organization and meaning
- Site design and layout is straightforward and concise
- Site design and layout are redundant only when required for user productivity
- White space is sufficient; pages are not too dense
- Unnecessary animation is avoided
- Colors used for visited and unvisited links are easily seen and understood
- Bold and italic text is used sparingly
Send questions, comments, and suggestions to usability-team@mit.edu
