What is the required page width for testing “Resize Text”?

Currently, there is no specific page width identified within the WCAG for Success Criteria 1.4.4: Resize Text. However, we do believe that there should be one and hope there will be one eventually, since there are instances where content on pages is lost at 200% zoom at some widths and not others.

For consistency’s sake and because it is not possible to test at every possible page width, we start the test at a browser window width of 1280 CSS pixels and then zoom to 200%. We use 1280 CSS pixels as our standard width because this width is specifically required by the WCAG for testing a page for Success Criteria 1.4.10: Reflow failures. For reflow failures, a tester starts at a 1280 CSS pixels browser width before zooming into 400%.

For additional help, the Guided Manual WCAG Audit Tool from Accessible Web includes a step to help automatically adjust your browser width for these types of manual tests.

Summary

There is not a required page width when zooming into 200% to test for Success Criteria 1.4.4: Resize Text. At Accessible Web, we test by starting at a browser window width of 1280 CSS pixels and zoom to 200% from there. This is to ensure consistency and because it is not possible to test at all widths. We hope that WCAG will define a required page width in the future.