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+[Back to 1 Perceivable index](index.md)
+
+# 1.4.6 Contrast (Enhanced)
+
+- Level: AAA
+- Guideline: 1.4 Distinguishable
+- Principle: 1 Perceivable
+
+## What it is
+
+The visual presentation of text and images of text has a contrast ratio of at least 7:1, except for the following:
+
+- **Large Text:** Large-scale text and images of large-scale text have a contrast ratio of at least 4.5:1;
+- **Incidental:** Text or images of text that are part of an inactive user interface component, that are pure decoration, that are not visible to anyone, or that are part of a picture that contains significant other visual content, have no contrast requirement.
+- **Logotypes:** Text that is part of a logo or brand name has no contrast requirement.
+
+## How to test
+
+- Check: Large-scale text and images of large-scale text have a contrast ratio of at least 4.5:1;
+- Check: Text or images of text that are part of an inactive user interface component, that are pure decoration, that are not visible to anyone, or that are part of a picture that contains significant other visual content, have no contrast requirement.
+- Check: Text that is part of a logo or brand name has no contrast requirement.
+- Use the sufficient techniques below as acceptable methods when applicable.
+- Confirm none of the common failures apply.
+
+## Sufficient techniques (W3C)
+
+- G17: Ensuring that a contrast ratio of at least 7:1 exists between text (and images of text) and background behind the text
+- G148: Not specifying background color, not specifying text color, and not using technology features that change those defaults
+- G174: Providing a control with a sufficient contrast ratio that allows users to switch to a presentation that uses sufficient contrast
+- G18: Ensuring that a contrast ratio of at least 4.5:1 exists between text (and images of text) and background behind the text
+
+## Advisory techniques (W3C)
+
+- G156: Using a technology that has commonly-available user agents that can change the foreground and background of blocks of text
+
+## Common failures (W3C)
+
+- F24: Failure of Success Criterion 1.4.3, 1.4.6 and 1.4.8 due to specifying foreground colors without specifying background colors or vice versa
+- F83: Failure of Success Criterion 1.4.3 and 1.4.6 due to using background images that do not provide sufficient contrast with foreground text (or images of text)
+
+## Resources
+
+- WCAG 2.2 SC: https://www.w3.org/TR/WCAG22/#contrast-enhanced
+- Understanding: https://www.w3.org/WAI/WCAG22/Understanding/contrast-enhanced.html
+- Quick reference: https://www.w3.org/WAI/WCAG22/quickref/?versions=2.2#contrast-enhanced
+
+[Back to 1 Perceivable index](index.md)