Editing Web colors (section)

===Color contrast===
The [[Web Content Accessibility Guidelines]] recommend a contrast ratio of at least 4.5:1 between the [[relative luminance]] of text and its background color<ref>[https://www.w3.org/TR/2008/REC-WCAG20-20081211/#visual-audio-contrast WCAG 2.0 guideline 1.4]</ref> or at least 3:1 for large text.  Enhanced accessibility requires contrast ratios greater than 7:1.

However, addressing accessibility concerns is not simply a matter of increasing the contrast ratio.  As a report to the [[Web Accessibility Initiative]] indicates,<ref>[https://www.w3.org/WAI/RD/2012/text-customization/r11 Optimal Colors to Improve Readability for People with Dyslexia]</ref> [[dyslexic]] readers are better served by contrast ratios below the maximum.  The recommendations they refer to of off-black (#0A0A0A) on off-white (#FFFFE5) and black (#000000) on creme (#FAFAC8) have contrast ratios of 11.7:1 and 20.3:1 respectively.  Among their other color pairs, brown (#282800) on dark green (#A0A000) has a contrast ratio of 3.24:1, which is less than the [[Web Content Accessibility Guidelines|WCAG]] recommendation, dark brown (#1E1E00) on light green (#B9B900) has a contrast ratio of 4.54:1 and blue (#00007D) on yellow (#FFFF00) has a contrast ratio of 11.4:1.  The colors named in the report use different color values than the web colors of the same name.