Understanding WCAG 2.0

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Images of Text:
Understanding SC 1.4.5

1.4.5 Images of Text: If the technologies being used can achieve the visual presentation, text is used to convey information rather than images of text except for the following: (Level AA)

  • Customizable: The image of text can be visually customized to the user's requirements;

  • Essential: A particular presentation of text is essential to the information being conveyed.

Note: Logotypes (text that is part of a logo or brand name) are considered essential.

Intent of this Success Criterion

The intent of this Success Criterion is to encourage authors who are using technologies that are capable of achieving a specific visual presentation to enable people who require a particular visual presentation of text to be able to adjust the text presentation as required. This includes people who require the text in a particular font size, foreground and background color, font family, line spacing or alignment.

If an author can use text to achieve the same visual effect, he or she should present the information as text rather than using an image. If for any reason, the author cannot format the text to get the same effect, the effect won't be reliably presented on the commonly available user agents, or using a technology to meet this criterion would interfere with meeting other criterion such as 1.4.4, then an image of text can be used. This includes instances where a particular presentation of text is essential to the information being conveyed, such as type samples, logotypes, branding, etc. Images of text may also be used in order to use a particular font that is either not widely deployed or which the author doesn't have the right to redistribute, or to ensure that the text would be anti-aliased on all user agents.

Images of text can also be used where it is possible for users to customize the image of text to match their requirements.

Techniques for satisfying this Success Criterion are the same as those for Success Criterion 1.4.9, except that they only need to apply if the visual presentation can be achieved with the technologies that the author is using. For Success Criterion 1.4.9, the sufficient techniques would be applied only when the user can customize the output.

See also Understanding Success Criterion 1.4.9 Images of Text (No Exception).

Specific Benefits of Success Criterion 1.4.5:

  • People with low vision (who may have trouble reading the text with the authored font family, size and/or color).

  • People with visual tracking problems (who may have trouble reading the text with the authored line spacing and/or alignment).

  • People with cognitive disabilities that affect reading.

Examples of Success Criterion 1.4.5

Related Resources

Resources are for information purposes only, no endorsement implied.

Techniques and Failures for Success Criterion 1.4.5 - Images of Text

Each numbered item in this section represents a technique or combination of techniques that the WCAG Working Group deems sufficient for meeting this Success Criterion. The techniques listed only satisfy the Success Criterion if all of the WCAG 2.0 conformance requirements have been met.

Sufficient Techniques

  1. C22: Using CSS to control visual presentation of text (CSS)

  2. C30: Using CSS to replace text with images of text and providing user interface controls to switch (CSS)

  3. G140: Separating information and structure from presentation to enable different presentations

Additional Techniques (Advisory) for 1.4.5

Although not required for conformance, the following additional techniques should be considered in order to make content more accessible. Not all techniques can be used or would be effective in all situations.

General techniques for non-text content

  1. Identifying informative non-text content (future link)

CSS Techniques

  1. C12: Using percent for font sizes (CSS)

  2. C13: Using named font sizes (CSS)

  3. C14: Using em units for font sizes (CSS)

  4. C8: Using CSS letter-spacing to control spacing within a word (CSS)

  5. C6: Positioning content based on structural markup (CSS)

  6. Avoid applying text styling to text characters within a word (future link)

Common Failures for SC 1.4.5

The following are common mistakes that are considered failures of Success Criterion 1.4.5 by the WCAG Working Group.

(No failures currently documented)

Key Terms

essential

if removed, would fundamentally change the information or functionality of the content, and information and functionality cannot be achieved in another way that would conform

image of text

text that has been rendered in a non-text form (e.g., an image) in order to achieve a particular visual effect

Note: This does not include text that is part of a picture that contains significant other visual content.

Example: A person's name on a nametag in a photograph.

text

sequence of characters that can be programmatically determined, where the sequence is expressing something in human language

visually customized

the font, size, color, and background can be set

This Web page is part of Understanding WCAG 2.0: A guide to understanding and implementing WCAG 2.0. The entire document is also available as a single HTML file. See the The WCAG 2.0 Documents for an explanation of how this document fits in with other Web Content Accessibility Guidelines (WCAG) 2.0 documents.

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