Readability: accessibility for content authors

  • Author: Access iQ ®
  • Date: 27 Nov 2012
  • Access: Premium

The purpose of Guideline 3.1 Make text content readable and understandable is to ensure text web content can be read and understood by the widest possible range of users with or without the use of assistive technologies.

The success criteria for this guideline require content authors and editors to take into account and address aspects of text presentation including language, unfamiliar or unusual words (jargon), abbreviations and acronyms, and instances where pronunciation affects the understanding of meaning.

There is one other success criterion associated with this guideline which addresses the reading level required for users to understand the text.

Success Criterion 3.1.5 Reading level states:

When text requires reading ability more advanced than the lower secondary education level after removal of proper names and titles, supplemental content, or a version that does not require reading ability more advanced than the lower secondary education level, is available. (Level AAA)

There are a couple of elements of this criterion that require explanation.

First, note that proper names and titles are excluded from this success criterion as it is agreed that it is not possible to modify such words without their meaning being lost. So, it does not apply to all text.

Second, this criterion specifies that an easy-to-read version of text is provided, as a supplement to the original text. So, the focus is more on providing alternate text that is easy to understand, rather than modifying the original text.

Lastly, this is one of the few WCAG 2.0 success criteria that refers to and depends on a specific external standard — in this case, a level of reading ability on the part of the user as defined in the International Standard Classification of Education (ISCE) adopted by the United Nations Educational, Scientific and Cultural Organisation (UNESCO).

That level is "lower secondary", which is defined as a reading level that can be expected to be attained after nine years of schooling.

The adoption of the ISCE standard is important. What it flags is that the WCAG Working Group could not identify a way of testing reading level successfully without referring to an external standard. Testability is a fundamental part of the WCAG approach: you must be able to test in order to meet the Success Criteria.

There are several techniques that are regarded as sufficient to meet Success Criterion 3.1.5 Reading level.

Provide a text summary

You may find it appropriate to summarise the key concepts and ideas in your web content in a short statement that is deliberately written using shorter sentences and simpler words than the original. This is provided as a supplement to the original text not as a replacement.

The summary can be provided direct on the web page in question or linked to as an external document.

You may this technique is helpful to all users of your web content. A simple summary is a powerful tool to keep your audience engaged, no matter what their reading level.

Use visuals

People with disabilities that make it difficult for them to understand complex words and sentences may benefit from the key concepts being expressed visually, in illustrations, photos, charts, graphs, videos and other visual materials. Note that each of these has accessibility considerations of their own that should be taken into account.

Since visual materials serve an additional purpose of breaking up large slabs of text, making such text more digestible and comprehensible to people of all reading abilities, it is again worth considering adding such visual elements to your web content as a matter of course.

Provide a spoken version

Having text read aloud is beneficial not only to people with impaired vision but also to people who have trouble sounding out long or complex words.

The suggested technique is most appropriate for text that is unlikely to change often (thus not requiring frequent updating), and can be presented as an audio file linked to from the webpage by a suitably marked up button or text link.

Many web authors, particularly those working with information to be presented to the community as a whole, are adopting this technique as another standard option along with making text available in community languages.

Make the text easier to read

It is definitely worth considering whether it is possible to use short words and sentences to express simple concepts, which together can be used to express complex ideas. There is no hard and fast rule on this — which simple reflects the almost immeasurable range of user needs and abilities — but it is fair to say that web content which is intended to be consumed by a wide range of users should be written in plain language.

Some of what may contribute to a plain language approach is covered in other sections of this guide, particularly the use of jargon and unusual words, acronyms and abbreviations, and making pronunciation clear. There are also many web resources that focus on clarity in writing web content.

It is important to note that it is not a requirement that all text content be presented in plain language. There are times when content is written for a specific audience, the members of which are not only comfortable with complex language, but who would lose some meaning if the language was made simpler.

What Success Criterion 3.1.5 does require is that such content is also made available in language that is easier to read. Even members of a highly educated user group with very specific interests may include people whose understanding of text web content is impeded by it being presented in complex words and sentences. Using accessibility techniques in this way is to adopt an inclusive approach.

Provide a sign language version

Providing a version of text content in sign language may make it more accessible to people whose first language is sign. This raises several attendant issues.

First, given the nature of how web content is provided to a user, the only realistic way to provide sign language version of text content is by way of a video. This means the content author must understand how to implement web video in an accessible way, and provide the user with controls to turn the video on and off.

It also becomes necessary to choose which sign language to use. If the web content is aimed at a primary user group, then the sign language of that group should be used. For example, an Australian local government website aimed at local residents would use Auslan. If a site is aimed at multiple audiences, consideration should be given to providing multiple sign language versions.

Note: it is not required to synchronise such a video of a sign language version of the text with the rest of the web page, since this is supplementary content, an alternative version of the original content.


A major consideration when meeting Success Criterion 3.1.5 is how to establish the reading level of your text content. If you do not have any access to the expertise required to judge the reading level of your web content, you may need to bring that expertise in from outside.

Web accessibility professionals should have the expertise to do this, but you may also find that a qualified teacher is able to analyse your text and provide guidance on its reading level.

You may also find that the readability gauges built into the spell checkers of some document processing software is sufficient for this purpose. There are also some online tools of varying reliability. Ultimately, user testing is your best guide.

It is also important to be aware that, in determining the wording of this guideline and its success criteria, the WCAG Working Group accepted that it may not be possible to make all text content readable enough for all people with all types and levels of disability.

WCAG 2.0 references

Related Techniques for WCAG 2.0