Let readers pick their own text colors
G175 puts a color picker on the page, covering the full range, so a reader can choose their own foreground and background and have the page adopt it. Saving the choice is not a nicety here. W3C's applicability line scopes the technique to technologies that can store preferences for reuse on other pages, and the description requires pages to look for those preferences and adapt when they find them. A picker that forgets is not this technique. W3C lists it as sufficient for 1.4.8 Visual Presentation, at Level AAA, and nowhere else. The people W3C names are specific too. Some readers with cognitive disabilities cannot read standard black on white and need combinations nobody else would predict, such as brown on blue, and often cannot manage browser or system settings themselves.
How we find it in an audit
Our reviewers open the picker and check what it actually reaches. Three preset themes is not a full color range. Then we set an unusual pair, move to another page, and come back the next day to see whether the choice survived. We also check whether the setting applies to the body text or only to the chrome around it.
How affected users experience it
A person who reads comfortably in brown on blue is not going to find that combination in a theme menu, and may not be able to set it in the operating system either. An on-page picker is the only place they can get it. When the site remembers it, the whole site becomes readable in one action. When it does not, they set it again on every page until they stop coming.
Passes vs. fails
Passes
A 'Display settings' panel with foreground and background pickers covering the full color range, applied to all text and remembered on return visits.
Fails
A 'theme' menu offering light grey, lighter grey and dark mode, which restyles the header and leaves article text hard-coded.
Other ways to satisfy this rule
21 guides on this site are filed under 1.4.8 Visual Presentation. W3C lists this one as sufficient for that rule on its own. Implement it correctly, in a way your readers' software actually supports, and the rule is met.
- C12sufficientSize text in percent so it scales
- C13sufficientUse named font sizes that respect user defaults
- C14sufficientSize text in em units, not pixels
- C19sufficientAlign text left or right, never justified
- C20sufficientCap line length with relative column widths
- C21sufficientGive paragraphs breathing room with line spacing
This guide is our interpretation of W3C technique G175: Providing a multi color selection tool on the page for foreground and background colors. W3C publishes its techniques as guidance rather than as the standard, and says so on every one of them. The success criterion is what conformance is measured against, and a technique is one documented way to meet it.