Shift colors to make text and images visible with certain types of color blindness

This feature allows users to (via installed software or online services) convert colored text and images so that colors are distinguishable to those with certain types of colorblindness. For example, a site with green text on a red background may be very difficult, if not impossible, to read by someone with red-green colorblindness, but a simple conversion to green on white could solve the problem.

Discussion by Disabilities (Benefits & Preferred Behaviors)

Low Vision

Enables users to see text that is otherwise invisible due to certain types of colorblindness.

Existing Products

This listing includes a wide range of products, from screen readers, to simple text-to-speech utilities, to large literacy suites that include a text-to-speech application. Please note that these products are not necessarily endorsed by RtF, but represent the range of available options.

Open Source and free

These products are free and their source code may be modified with few restrictions.

  • ATbar – ATbar, University of Southampton

Free, not necessarily open source

These products are free to use, but may have strict restrictions on viewing and modifying source code.

Commercial, with free trial

These products are free to try for a limited period of time or with limited functionality. They must be purchased for full functionality.

Related Research and Papers

Learn more about low vision, its causes, types and impact on everyday life.


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