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checklist for accessibility

This checklist for accessibility is based on the WAI (Web Accessibility Initiative) of the W3C. Items are categorized and weighted. At the moment this form is not live, so you have to add the weight manually and then divide by the number of items to determine the percentage of accessibility, hence basic usability.

This is a qualitative test.

OF = Optional Feature, which does not mean the checkpoint is optional, but that the feature may perhaps not be used in a web document. However, when the feature does appear, the criterion must be applied.

User control

  Yes Weight
Provide information so that users may receive documents according to their preferences (e.g., language, content type, etc.) 1
Provide keyboard shortcuts to important links (including those in client-side image maps), form controls, and groups of form controls. 1
Create a logical tab order through links, form controls, and objects. 1


Document language Yes Weight
Clearly identify changes in the natural language of a document's text and any text equivalents (e.g., captions). 6
Identify the primary natural language of a document. 1
Language use    
Specify the expansion of each abbreviation or acronym in a document where it first occurs. 1
Use the clearest and simplest language appropriate for a site's content. 6

Content structures

Information chunking Yes Weight
Divide large blocks of information into more manageable groups where natural and appropriate. 3
Place distinguishing information at the beginning of headings, paragraphs, lists, etc. 1
Use header elements to convey document structure and use them according to specification. 3
Mark up quotations. Do not use quotation markup for formatting effects such as indentation. OF 3
Mark up lists and list items properly. OF 3


Color Yes Weight
Ensure that all information conveyed with color is also available without color, for example from context or markup. 6
Ensure that foreground and background color combinations provide sufficient contrast when viewed by someone having color deficits or when viewed on a black and white screen. 1
Organize documents so they may be read without style sheets. For example, when an HTML document is rendered without associated style sheets, it must still be possible to read the document. 6
Use style sheets to control layout and presentation. 3
Create a style of presentation that is consistent across pages 1
Until user agents allow users to turn off spawned windows, do not cause pop-ups or other windows to appear and do not change the current window without informing the user. OF 3


Navigation Yes Weight
Use navigation mechanisms in a consistent manner. 3
Provide navigation bars to highlight and give access to the navigation mechanism. 1
Group related links, identify the group (for user agents), and, until user agents do so, provide a way to bypass the group. 1
Clearly identify the target of each link. 3
Until user agents (including assistive technologies) render adjacent links distinctly, include non-link, printable characters (surrounded by spaces) between adjacent links. 1
Site map    
Provide information about the general layout of a site (e.g., a site map or table of contents). 3

Behind the scenes

Metadata Yes Weight
Provide metadata to add semantic information to pages and sites. 3
Search facility    
If search functions are provided, enable different types of searches for different skill levels and preferences. OF 1

W3C recommendations

W3C recommendations Yes Weight
Use W3C technologies when they are available and appropriate for a task and use the latest versions when supported. 3
Avoid deprecated features of W3C technologies. 3
Create documents that validate to published formal grammars. 3
Replace view    
Until user agents provide the ability to stop the refresh, do not create periodically auto-refreshing pages. 3
Until user agents provide the ability to stop auto-redirect, do not use markup to redirect pages automatically. Instead, configure the server to perform redirects. 3


Alternative page Yes Weight
If, after best efforts, you cannot create an accessible page, provide a link to an alternative page that uses W3C technologies, is accessible, has equivalent information (or functionality), and is updated as often as the inaccessible (original) page. OF 6
Document collections    
Provide information about document collections (i.e., documents comprising multiple pages.). 1

More complex markup

These features do not appear in text-only documents, but in documents that contain structural features such as tables and frames, or embedded objects (such as images). They are thus Optional Features that require slightly more complex markup than used for text-only documents.

Features are optional;
tests are not optional when a feature does occur
Alternate Text Yes Weight
Provide a text equivalent for every non-text element (e.g., via "alt", "longdesc", or in element content). This includes: images, graphical representations of text (including symbols), image map regions, animations (e.g., animated GIFs), applets and programmatic objects, ASCII art, frames, scripts, images used as list bullets, spacers, graphical buttons, sounds (played with or without user interaction), stand-alone audio files, audio tracks of video, and video. 6
Object dimensions    
Use relative rather than absolute units in markup language attribute values and style sheet property values. 3
Until user agents allow users to control flickering, avoid causing the screen to flicker. 6
Until user agents allow users to control blinking, avoid causing content to blink (i.e., change presentation at a regular rate, such as turning on and off). 3
Images and image maps    
Ensure that foreground and background color combinations provide sufficient contrast when viewed by someone having color deficits or when viewed on a black and white screen. 3
When an appropriate markup language exists, use markup rather than images to convey information. 3
Provide redundant text links for each active region of a server-side image map. 6
Provide client-side image maps instead of server-side image maps except where the regions cannot be defined with an available geometric shape. 6
Until user agents render text equivalents for client-side image map links, provide redundant text links for each active region of a client-side image map 1
Supplement text with graphic or auditory presentations where they will facilitate comprehension of the page. 1
Provide a means to skip over multi-line ASCII art. 1
For data tables, identify row and column headers. 6
For data tables that have two or more logical levels of row or column headers, use markup to associate data cells and header cells. 6
Do not use tables for layout unless the table makes sense when linearized. Otherwise, if the table does not make sense, provide an alternative equivalent (which may be a linearized version). 3
If a table is used for layout, do not use any structural markup for the purpose of visual formatting. 3
Provide summaries for tables. 1
Provide abbreviations for header labels. 1
Until user agents (including assistive technologies) render side-by-side text correctly, provide a linear text alternative (on the current page or some other) for all tables that lay out text in parallel, word-wrapped columns. 1
Until user agents support explicit associations between labels and form controls, for all form controls with implicitly associated labels, ensure that the label is properly positioned. 3
Associate labels explicitly with their controls. 3
Until user agents handle empty controls correctly, include default, place-holding characters in edit boxes and text areas. 1
Title each frame to facilitate frame identification and navigation. 6
Describe the purpose of frames and how frames relate to each other if it is not obvious by frame titles alone. 3
Applets and scripts    
Ensure that pages are usable when scripts, applets, or other programmatic objects are turned off or not supported. If this is not possible, provide equivalent information on an alternative accessible page. 6
For scripts and applets, ensure that event handlers are input device-independent. 3
Until user agents allow users to freeze moving content, avoid movement in pages. 3
Functional applets and scripts: Make programmatic elements such as scripts and applets directly accessible or compatible with assistive technologies 6
Applets and scripts for other purposes: Make programmatic elements such as scripts and applets directly accessible or compatible with assistive technologies 3
Ensure that any element that has its own interface can be operated in a device-independent manner. 3
For scripts, specify logical event handlers rather than device-dependent event handlers. 3
Until user agents can automatically read aloud the text equivalent of a visual track, provide an auditory description of the important information of the visual track of a multimedia presentation. 6
For any time-based multimedia presentation (e.g., a movie or animation), synchronize equivalent alternatives (e.g., captions or auditory descriptions of the visual track) with the presentation. 6
Dynamic sites    
Ensure that equivalents for dynamic content are updated when the dynamic content changes. 6
Ensure that dynamic content is accessible or provide an alternative presentation or page. 3


  Yes Weight
Percentage accessibility conformance   %