Email Client Zoom Support


April 2019


62 time


One of the success criteria's for WCAG 2.1 AA, is to support the use of the browser zoom feature, up to 200%. Was wondering if anyone knew of a similar criteria that needed to be met for email clients? WCAG doesn't seem to specify one way or another with regards to email.

1 answers


If you want accessibility requirements for non-web based applications, the document you are looking for is not WCAG 2.0 or 2.1 but Guidance on Applying WCAG 2.0 to Non-Web Information and Communications Technologies (WCAG2ICT). This document was finalised in 2013 and it is not clear whether it will be updated to reflect the additions in WCAG 2.1.

The specific criterion you are looking for is still 1.4.4: Resize text (Level AA), but this time in WCAG2ICT. More specifically, you should look at the second note of the additional guidance:

Note 2: The Intent section refers to the ability to allow users to enlarge the text on screen at least up to 200% without needing to use assistive technologies. This means that the application provides some means for enlarging the text 200% (zoom or otherwise) without loss of content or functionality or that the application works with the platform features that meet this requirement.

Of course, if the e-mail client is web-based (i.e. web-mail), then WCAG 2.1, SC 1.4.4 applies, but it is sufficient if a browser zoom to 200% does not cause a loss of content or functionality.

Note that WCAG2ICT is "only" a "WC3 Note", not a "W3C Recommendation"; in that sense, it is not a standard.