The Colour Contrast Analyser is compatible with the Web Content Accessibility Guidelines version 2 (WCAG 2.0). The tool was developed by JUn of the Web Accessibility Tools Consortium in collaboration with Vision Australia and Steve Faulkner of The Paciello Group (Europe).
What is the Colour Contrast Analyser?
It is primarily a tool for checking foreground & background colour combinations to determine if they provide good colour visibility. It also contains functionality to create simulations of certain visual conditions such as colour blindness.
The contrast ratio helps determine whether or not the contrast between two colours can be read by people with colour blindness or other visual impairments.
WCAG 2.0 Conformance
The Colour Contrast Analyser is useful to help determine the legibility of text on a web page or document, and the legibility of image based representations of text against WCAG 2.0 requirements.
Guideline 1.4 Distinguishable: Make it easier for users to see and hear content including separating foreground from background. WCAG 2.0
Guideline 1.4.3: Contrast (Minimum)
The visual presentation of text and images of text has a contrast ratio of at least 4.5:1, except for the following:
- Large Text: Large-scale text and images of large-scale text have a contrast ratio of at least 3:1;
- 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 minimum contrast requirement. (Level AA)
Guideline 1.4.6: Contrast (Enhanced)
The visual presentation of text and images of text has a contrast ratio of at least 7:1, except for the following: (Level AAA)
- 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 Logotypes: Text that is part of a logo or brand name has no minimum contrast requirement.
The Colour Contrast Analyser has been optimised for IE and Firefox.
For Mac and alternate versions of the Colour Contrast Analyser visit The Paciello Group website.
The Colour Contrast Analyser is Freeware.
You may use the Colour Contrast Analyser Software (the "Software") for your personal or commercial use to help you determine the accessibility of your Web content.
THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR IMPLIED WARRANTY. IN PARTICULAR, THE WEB ACCESSIBILITY TOOLS CONSORTIUM (WAT-C) DOES NOT MAKE ANY REPRESENTATION ORWARRANTY OF ANY KIND CONCERNING THE RELIABILITY, QUALITY, OR MERCHANTABILITY OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR PURPOSE. ADDITIONALLY, WAT-C DOES NOT GUARANTEE THAT USE OF THIS SOFTWAREWILL ENSURE THE ACCESSIBILITY OF YOUR WEB CONTENT OR THAT YOUR WEB CONTENT WILL COMPLY WITH ANY SPECIFIC WEB ACCESSIBILITY STANDARD.
We value all feedback received. Please contact the developers about any functionality that may not work or other suggestions for improvement.
This work is licenced under a Creative Commons Licence