Sim Daltonism - From the perspective of a color blind person, some colors are impossible to distinguish.

TestRail - TestRail provides comprehensive test case management for software testing. Organize your testing, boost productivity, get real-time insights, and track progress toward milestones. Integrates with leading issue tracking and test automation tools.

Coblis - If you are not suffering from a color vision deficiency it is very hard to imagine how it looks...

Micro Focus ALM - Learn how Micro Focus’ Application Lifecycle Management (ALM) software tools provide the agility, visibility, and collaboration solutions you need to optimize app development and testing, foster innovation, and improve the user experience.

Colorblind Web Page Filter - Enter a URL, and this tool will render it as someone with color blindness will see it.

Helix ALM - Helix ALM is the single, integrated application that lets you centralize and manage requirements, test cases, issues, and other development artifacts and their relationships.