Sim Daltonism - From the perspective of a color blind person, some colors are impossible to distinguish.
LinkChecker - LinkChecker is a free, GPL licensed website validator.
Colour Blindness Simulator - Use our Colour Blindness Simulator to reveal how your images may appear to users with a variety of...
Pulno - SEO Audit and Website Analysis. Pull up your SEO.
Colorblind Web Page Filter - Enter a URL, and this tool will render it as someone with color blindness will see it.
Checkbot - Checkbot will boost the SEO, speed and security of your site by checking you're following 50+ web best practices. Browser extension with free and paid plans.