accessgarage.wordpress.com/2013/02/09/458/

This tool is a Free Vision Simulator for Chrome

https://achecker.ca/projects-and-tools/

This tool checks single HTML pages for conformance with accessibility standards addons.

http://www.standards-schmandards.com/projects/fangs/

This tool renders a text version of a web page similar to how a screen reader would read it

contrast-­finder.tanaguru.com

This tool tests the colour contrast of a site

nvaccess.org/download/

This site provides a free screen reader to test your site for low vision accessibility

snook.ca/technical/colour_contrast/colour.html

This tool allows you to specify a foreground and a background colour and determine if they provide enough contrast when viewed by someone with colour deficits or when viewed on a black and white screen

squizlabs.github.io/HTML_CodeSniffer

This tool checks that HTML code conforms to a coding standard

wave.webaim.org

This site provides a web accessibility evaluation tool

validator.w3.org

This validator checks the markup validity of web documents in HTML, XHTML, SMIL, MathML, etc