Test that text sizes and zooms correctly

For: Development, Design

Resize text (1.4.4 level AA)


People use their browser to change the size of content, and people with low vision may use that to a more extreme level.

Texts and text containers should be in relative units (percent, em, rem) rather than in pixels to allow resizing.

Users can also override the font-family and spacing for text, which can also break a fragile layout.

Check what content and functionality you can see when:

  • Size your browser window to 1280px wide and zoom into 400% (Firefox and Chrome - go to settings).
  • Resize text only to 200% (32pt) (Firefox and Chrome - go to settings).
  • Check that you can still see all the content and functionality, even if it involves opening show/hide elements or clicking through to another page.

Text spacing (1.4.12 level AA)


  • Activate the text spacing bookmarklet.
  • Check for missing or overlapping content and that there is no horizontal scrolling.
  • Gradually zoom out to 300%, then 200% then 100%, checking the text spacing at each stage.