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# 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

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