Developing Accessible Websites
In order to assure that websites and web applications are accessible and usable by everyone, it’s important that web accessibility guidelines are followed. The features listed are not intended to replace or map to formal standards within the World Wide Web Consortium’s (W3C’s) Web Content Accessibility Guidelines.
WCAG is organized around four key principles (P.O.U.R.):
- Perceivable – making sure users can perceive content. This helps us keep in mind that just because something is perceivable with one sense, such as sight, that doesn’t mean that all users can perceive it.
- Operable – can users use UI (user interface) components to navigate the content. For example, something which requires a hover interaction cannot be operated by someone who can’t use a mouse or is using a touchscreen.
- Understandable – Can users understand the content? Also, can all users understand the interface and is it consistent enough to avoid confusion?
- Robust – is it robust enough for the content to be consumed by a wide variety of user agents? Does it work with assistive technology?
Features of Accessible Websites
- Good use of HTML headings.
- Ensure page can be navigated with a keyboard.
- Provide alternative text descriptions to images.
- Use accessible menus.
- Design accessible form controls using labels, instructions, and validation/error messages.
- Use tables for data and use column headers.
- Use sufficient color contrast. Don’t convey content with color alone.
- Ensure link text makes sense on its own. Avoid ambiguous link text.
- Format lists as ordered or unordered lists.
- Watch the use of caps. All caps can be difficult to read and can be read incorrectly by screen readers.
- Identify document language.
30 Web Accessibility Tips
- Add proper alt text to images. Use alt text to provide access to the content of images for individuals who cannot see them, including people using screen readers or Braille output devices. Alt text is supported by most document formats, including HTML, Microsoft Word, and Adobe PDF.
- Use headings properly. Use headings and subheadings to form an outline of the page. They help non-visual users (including search engines) to understand how the page is organized, and make it easy for screen reader users to navigate.
- Create accessible PDFs. Tag content in PDFs, and take steps to ensure that the content will be read in the correct order.
- Know when to use PDF. PDF preserves a document’s appearance across operating systems and devices. If this characteristic is not essential, consider using an alternate format such as HTML.
- Use ARIA landmarks. The new Accessible Rich Internet Applications (ARIA) W3C specification makes it possible to produce accessible interactive web applications. One easy entry into ARIA is landmark roles. Simply add an HTML attribute for one of the eight landmark roles (e.g., role=”navigation”, role=”main”) and users will be able to jump directly to a section of the page with a single keystroke.
- Add labels to form fields. In HTML, use the <label> element and in PDF, use tooltips so that non-visual users will know which labels or prompts are associated with form fields.
- Group related form fields together and assign a single prompt that they all share. When creating a form with checkboxes and radio buttons, use <fieldset> as a container for the group of fields and <legend> for the group prompt. (There are similar techniques in PDF.)
- Markup tables appropriately. Use HTML markup properly to explicitly communicate relationships between column and row headers and the data cells within their scope.
- Identify language of text. Since some screen readers are multi-lingual; use markup to identify the default language of a document and of any text that deviates from the default.
- Use a color contrast checker. Be sure foreground and background have adequate contrast. There are many free tools that can help with this.
- Avoid using tiny fonts. Since users may be unaware they can increase font size using browser hot keys, use a reasonably large font size by default; then, users can make it smaller if desired. Note that a font size of 1em uses the default browser font size.
- Respect white space (between lines, between paragraphs). Providing plenty of space between lines and blocks of text can help users who have difficulty tracking text horizontally. Adequate white space also contributes to a cleaner, more aesthetically pleasing interface for everyone.
- Provide visible indication of focus, especially for keyboard users. In CSS, use :hover to make the page come alive, responding to user’s mouse movements. For people who aren’t using a mouse, provide the same functionality using :focus.
- Use text, not pictures of text. Use text instead of pictures of text, and control its appearance using CSS. Pictures of text become blurry when enlarged, take longer to download, and are inefficient for the website author to edit.
- Think twice about the words you choose. Keep your content simple to read and understand. Often web authors use larger words and longer sentences than is really necessary.
- Caption video. Captions provide benefits to all users. There are many free, easy-to-use tools available that support the process of transcribing and captioning, videos.
- Describe video. For people are unable to see video, create a script that includes brief descriptions of important visual content, then provide that as a separate description track, either as timed text or recorded narration.
- Provide a transcript. Provide a transcript for video and audio so individuals who are deaf-blind and those with low Internet bandwidth can access the content. Transcripts benefit all users by allowing them to access content quickly.
- Choose media players that support accessibility. Ask questions like: Does this player support closed captions? Does it support description? Can it be operated with a mouse? Are buttons and controls accessible to screen reader users?
- Choose a dropdown menu system that works for all users. Ask questions like: Can this menu be operated by keyboard alone? If so, is doing so efficient or does it require dozens or hundreds of keystrokes?
- Choose Learning Management Systems (LMS) and Content Management Systems (CMS) that support accessibility. Make sure that your organization’s LMS or CMS supports accessibility. Make sure there are accessible themes, plug-ins, and modules available that will meet your needs.
- Test web pages with a keyboard. Try navigating the web page and controlling all its features using the tab key on a keyboard; don’t touch the mouse. This simple test is typically a good indicator of accessibility.
- Test pages with high contrast color schemes. All major operating systems have high contrast color schemes available. When it is enabled, make sure that all important page content is still visible.
- Test pages with assistive technologies. There are free screen readers and other AT available that can be used for testing. You don’t have to become an expert user, but simple tests with AT can provide valuable insights into whether certain features in a document might present accessibility problems.
- Test pages on mobile devices. Growing numbers of users, including users with disabilities, are accessing the web using phones, tablets, and other mobile devices. Test your website using several mobile devices.
- Ask vendors specific questions about the accessibility of their products. “Is your product accessible?” is not a good question. Ask them to demonstrate how their product can be used without a mouse or with a screen reader. Ask about their methods for testing accessibility.
- Demand accessibility! If a product is not accessible, avoid buying it, using it, or supporting it. Work to implement policies on your campus that require IT purchases to be accessible. If it is required that an inaccessible product be used because it is the only current alternative, put the vendor on notice that you expect to purchase an accessible alternative when it becomes available.
- Get involved! There are many communities of practice that are working together on making the web (and world) more accessible. Together we can make a difference!
Download 30 Web Accessibility Tips PDF.