Who Can Use - WhoCanUse is a tool that brings attention and understanding to how color contrast can affect different people with visual impairments.
accessiBe - Making websites accessible to people with disabilities
Cron Color - Free web tool for designing color palettes and checking contrasts.
Page Speaker - Modern web accessibility tools for agencies & webmasters
Kontrast - Check and adjust web element contrast in real time.
Koa11y - Automatically detect accessibility (a11y) issues on webpages