A colour contrast checker is a great tool for web accessibility. Text can be difficult to read when there isn’t enough contrast between the colour of a font and the background. Website standards ensure that the web is an accessible place and this includes visually. Search engines like Google factor in colour contrast into how they rank websites for SEO.
Use a colour contrast checker to test your website’s web accessibility, like the one over at WebAIM. Visit https://webaim.org/resources/contrastchecker/