There are loads of microsites and developer tools for looking at color accessibility, including tools built right into browser DevTools. They often show you if a color passes AA or AAA WCAG guidelines. But color contrast is more complicated than that because there is a wide variety of vision impairments.
This site from Corey Ginnivan takes two colors and then shows you a simulation of different vision types (e.g. Tritanomaly, trouble distinguishing blues) and whether the colors still pass OK. Plus, situational events, like whether a screen is in direct sunlight.