The purpose of this success criterion is to ensure that users can reconfigure the text to better meet their reading needs, such as enlarging fonts to improve readability for users with low vision and changing the text alignment and word spacing to aid users with dyslexia.
How to Meet
As the widely available reading systems provide users the option to control most or all of the text properties specified in this success criterion, authors do not need to implement anything extra for reflowable EPUB content.
They do need to ensure that when text is resized to 2.0% that users do not have to scroll to read any complete line of text (it is okay if users must scroll to locate the text).
Fixed layout EPUBs cannot meet this success criterion as reading systems do not allow users to modify the publisher styles.
The following knowledge base pages provide more information about how to address this success criterion for publishing content: