Do you want to find out if the text color in your websites are readable enough or if  there is sufficient contrast between the background and the foreground color? then check out http://www.checkmycolours.com/

It calculates the Luminosity Constrast Ratio and the Color brigthness of all the DOM elements of your site and provides a detailed report of whether the site has failed or passed the test. so go ahead and give it a try..