Text contrast below minimum Accessibility Checkpoint

Description

Ensure that text and background colors have enough contrast.

Help

Some users find it hard to read light gray text on a white background, dark gray text on a black background and white text on a red background.

• The contrast ratio should be 3.0 or more for 18 point text, or larger
• The contrast ratio should be 3.0 or more for 14 point bold text, or larger
• The contrast ratio should be 4.5 or more for all other text

Applicable standards

• ACT Rules afw4f7
• WCAG 2.0 (Success Criteria: 1.4.3 level AA, 1.4.6 level AAA)
• WCAG 2.1 (Success Criteria: 1.4.3 level AA, 1.4.6 level AAA)
• WCAG 2.2 (Success Criteria: 1.4.3 level AA, 1.4.6 level AAA)
• Section 508 (2017) (Success Criteria: 1.4.3 level AA, 1.4.6 level AAA)

Note: Section 508 Refresh (2017) checkpoints are equivalent to WCAG 2.0 level A and level AA checkpoints.

Change history

• 6.54 Oct 2024 Fixed false positive.
• 6.52 Apr 2024 Improved detection.
• 6.48 Mar 2023 Improved detection.
• 6.47 Dec 2022 Now fires for form controls.
• 5.37 May 2020 Fixed false positive.
• 5.36 Jan 2020 Improved detection.
• 5.31 Nov 2018 Fixed false positive. Changed rule ID from AccWcag1-2.2.2 to AccHtmlContrastMinimum.
• 5.29 May 2018 Fixed false positive.
• 5.22 Jul 2016 Fixed false positive on print media.
• 5.21 Mar 2016 Fixed false positive.
• 5.20 Jan 2016 Better detection with transparent background colors, and bold text.
• 5.8 Mar 2015 Fixed false positive on some large scale text.
• 5.2 May 2013 Reports which browsers are affected by this issue.
• 5.1 Jan 2013 Corrected contrast ratio displayed in message detail - wrong number shown in some cases.
• 3.5 Dec 2009 Corrected priority.
• 3.0 Dec 2008 Now uses WCAG 2 color contrast algorithm and triggers WCAG 2 1.4.3.
• 1.0 Feb 2007 Added.

This page describes a web site issue detected in HTML documents by SortSite Desktop and OnDemand Suite.

Rule ID: AccHtmlContrastMinimum