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Appropriate Use of Colour

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This document is available in alternate formats upon request. Please contact the Accessibility Coordinator.

When using colour, you must make sure that any information conveyed with colour is also conveyed by another means. For example, including text with colour-coded icons will help to clarify the function of the icon. Marking required form fields in another way (either with an * before the field, using the word "required" after the form-field label) or using appropriate headers and contextual navigation in each distinct section of the web site will help to alleviate these colour-reliant issues.

Consider a form that indicates "all required fields are marked in red," a page that states "click the green button to continue," or a web-based report that shows status icons for transactions that differ only in their colour. In each of these cases, someone that may not be able to distinctly recognize certain colours because of their monitor settings, because of colorblindness, or because he/she is using a device that doesn't display colours would experience difficulty getting the information or completing the task at hand.

Colours and Cascading Style Sheets (C.S.S.)

Using style sheets for presentation is not without pitfalls. Because there are so many interacting style rules that are required to create a full web site, colours must be paired when they are declared in a style sheet. This ensures that there are always contrasting colours when the style sheet is applied to a document and, when the style sheet is not there or is overridden, that both foreground and background are affected. Design errors occur when text colour is determined by the style sheet while the background colour is declared directly in the HTML. As an example, when Cascading Style Sheets are turned off (via the user's browser settings) or not supported (alternative browser), this could result in default blue-coloured links laid out on a dark-coloured background, making the links impossible to read.

Thus, all colours should be declared in pairs in style sheets. Such a declaration may look like this:

a {color: red; background-color: transparent;}

Colour Contrast

You must provide high colour contrast to the text in your document. A good example of high colour contrast is black and white; while an example of poor colour contrast is light yellow and white.

Avoid blinking or scrolling text.

WCAG 2.0 Guideline 1.4.3

The visual presentation of text and images of text has a contrast ratio of at least 4.5:1, except for the following: (Level AA)

  • Large Text: Large-scale text and images of large-scale text have a contrast ratio of at least 3:1;
  • Incidental: Text or images of text that are part of an inactive user interface component, that are pure decoration, that are not visible to anyone, or that are part of a picture that contains significant other visual content, have no contrast requirement.
  • Logotypes: Text that is part of a logo or brand name has no minimum contrast requirement.

use good colour contrast and readable font size and don't use low colour contrast and small fonts

Colour Contrast Checkers

Formatting Text

Semantic structure

Preparing content for the web is much more than just copying text from your favourite word processor and pasting it into the framework of a web page. In order to ensure the greatest accessibility and widespread availability of web content, it is important to consider that there is more to the web page than the words and pictures that end up in a person's browser.

Web pages are built with HTML, a structural language that is used to denote the different structural parts of the document. HTML employs an extensive series of opening and closing tags to mark parts of the document as, for example, headings (<h1></h1>), unordered lists (<ul></ul>), ordered lists (<ol></ol>, and paragraphs (<p></p>). These tags don't appear in the final view of the web page, but are used by the various web software applications to interpret the intended format of the text for output to the end user.

To help clarify the term semantic further, consider that some HTML tags (such as the <strong> for bold text) are not considered semantic elements but are presentational elements, i.e. while they do alter the visual presentation of the text, they don't define the actual structure of the text.

Using semantically structured HTML and then changing the way that the HTML looks with Cascading Style Sheets results in the final version of the web page that looks aesthetically pleasing to people viewing the web page in a browser, and is logically structured, providing meaning to those that need it. Pages built this way are not only accessible to the largest possible audience, but are also well set for future revision of both style and content, and can be easily adapted to accommodate emerging technology and advancing web development standards.


San serif versus serif font. shows how serifs can cause issues

  • The need to separate content from design is the underlying foundation for accessibility, scalability, and future compatibility of all of your web content. For this reason, size declarations should be recorded in a site's style sheet, and not in the content page.
  • Try to use fonts that are legible and easier to read such as Verdana, Tahoma, Lucida Grande, Arial, Georgia or any san-serif font. San-serif fonts are more legible and will benefit more users from the outset, especially those with low vision. In general, sans serif fonts display better on computers and mobile devices.
  • Avoid using serif or script base fonts as these may be difficult to read and cause eye strain.
  • Try to use large font sizes. Avoid font sizes smaller than 9pt as they are difficult to read.
  • Avoid italics and underlining text other than hyperlinks.
  • Use <strong></strong> tags for bolded text.


Using Headings makes it easier for various adaptive technologies to navigate a document. Many people do not create Headings correctly, either making font sizes bigger or in bold rather than using the formats already provided by WebPublish. Heading need to be marked up in the html code. Heading levels should have a meaningful hierarchy and it is recommended to reserve H1 for the page title, H2 for major headings and H3 for major sub headings.


<h1>Queen’s University</h1>

<p>Located in Kingston, Ontario…</p>


Using WebPublish

While you’re editing a draft:

  1. Select the text you would like to make into a heading.

Select the desired format from the format menu drop-down list.

screenshot making a heading using the format drop-down list in Webpublish 2.