Except for captions and images of text, text can be resized without assistive technology up to 200 percent without loss of content or functionality. (Level AA).
This success criterion requires that the text – both static and that are part of user interface components that are visible to the users must be resizable (scalable) to 200% without the help of any assistive technologies like screen magnifiers. Even though the user agents like the browsers that meet UAG (User Agent Guidelines) 1.0 bear the responsibility of scaling or zooming the text up to 200%, it is the authors responsible for providing that support to the browsers.
What do I do as the content author?
The authors or developers have to ensure:
- The content is scalable to 200% without any loss of information or functionality
- The content or texts do not overlap or become not available to the users
- The user interface components do not become unusable or inactive.
Users with low vision or limited vision who consume the content without any assistive technology but use browsers’ zoom functionality alone.
Points to ponder
- Where browsers do not support or provide zoom functionality (IE6 as an example), provide alternative CSS for scaling purpose
- When zoomed to 200%, ensure there is no much of horizontal scrolling ( a best practice)
- Where lengthy user interface components or content like subject line of an email is there, truncate and provide ways along with the instructions to access the content.