Checkpoint 504.2.1: Preservation of Information Provided for Accessibility in Format Conversion

Authoring tools shall, when converting content from one format to another or saving content in multiple formats, preserve the information required for accessibility to the extent that the information is supported by the destination format.


When accessible content is created in one format, the accessible content and related information (such as proper heading mark-up) should be preserved when converting the document to another format.

The chief danger when converting is that the structure that improves a content's accessibility may be lost, yet the visual cues that suggest its presence continue to exist. For instance, properly structured and accessible heading levels may exist in the original format, but when saved as another format, although the appearance of heading styles may be preserved (for instance, they still appear centered in a larger type size) the structural information that designates them as headings is lost.

In such a situation, assistive technologies can no longer expose this heading information to the end user. As well, technologies will no longer be able to apply user-specified styling to the headings.

Other common conversion losses include tabular information which is no longer programmatically structured as a table, form fields which are no longer interactive or are no longer associated with their labels, and navigation elements which appear to be retained but are no longer functional.

Note: Some formats may not support all the accessibility information contained in the original. The requirement is to ensure the accessibility is preserved "to the extent that the information is supported by the destination format."

General techniques

Instructions: Where authoring tools support file conversion or saving to multiple formats, ensure that accessibility information is preserved. Each of the following Authoring Tool Accessibility Guidelines techniques can be used to help achieve this checkpoint.

Many links in this checklist reside outside at the Web Content Accessibility Guidelines (WCAG) 2.1. W3C Recommendation 05 June 2018:

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