Color contrast guideline subgroup

Basic Information

IRC channel: irc.w3.org channel: #wcag3-contrast

Lead: TBD, Contact the Accessibility Guidelines Working Group Planning group-ag-plan@w3.org for contact info

Prior Lead(s): Chris Loiselle

Working Documents

Current Work

• Color and Contrast scratchpad

Archive

The Visual Contrast of Text subgroup of the Silver Task Force wrote a guideline for the First Public Working Draft of WCAG3 to demonstrate a guideline with a significant change from WCAG2. The research and resulting algoritm requires extensive peer review from other researchers in color contrast before adoption. There is a lot of useful and insightful material on and linked from this subgroup page.

Prior work that may apply

Results of 2022 Analysis of WCAG2 that could apply to this guideline

WCAG2 Analysis Doc	SC Name
1.4.1	Use of Color (hue and colorfulness)
1.4.8a	Foreground and background colors of blocks of text can be selected by the user.
1.4.3	Contrast (Minimum)
1.4.6 (see 1.4.3)	Contrast (Enhanced)
1.4.3a	Contrast exceptions
1.4.3	Color Choices for Alternate Modes (Dark Mode, High Contrast, Daltonization)
1.4.1a	Use of color in controls
1.4.1b	Use of color in organizing content
1.4.11	Non-text Contrast - UI Components
1.4.11a	Non-text Contrast - Graphics
1.4.11b	Non-text Contrast - Dataviz
1.4.11c	Non-text use-cases: Semantic, Symbolic, DataViz, Container.
1.4.4	Content Zoom
1.4.4a	Proportional Text Zoom
1.4.6	Contrast (Enhanced)
1.4.6a	Font weight and glyph characteristics
1.4.6b	Text use cases: Fluent Body Text, fluent text, sub-fluent, spot-readable, ancillary.
1.4.8	Use of contrast in the visual hierarchy (was Visual Presentation)
1.4.8a	User selectable text and background colors for blocks of text.
1.4.8b	Column width for body-text is no more than 80 characters or glyphs (40 if CJK).
1.4.8c	Body-text is left justified for ltr reading, and right justified for rtl, Body text is never full-justfed. (aligned to both the left and right margins) nor center justified.
1.4.8d	Body-text line spacing (leading) is at least 2.5 times the x-height in paragraphs & paragraph spacing 1.5x line spacing.
1.4.8e	Sufficient margins and padding around text
1.4.5	Images of Text, where the text is part of content meets contrast minimums.
1.4.5a	SVG containing text, rich-text formatted alt-text.

Also noting a possible requirement for light/dark mode switching.

Minutes

• [List of links to minutes or note from all subgroup meetings with most recent minutes on top]

Referenced Research

• See the Visual Contrast of Text subgroup of Silver Task Force

Key Decisions Agreed on with Date

• [YY-MM-DD] - [decision brief description]

Participants

Current Participants

• TBD

Former Participants

• Chris
• Bruce
• Andy
• Todd L.
• Cybele
• Chuck