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

This tool is a Free Vision Simulator for Chrome

accessibility.oit.ncsu.edu/tools/color-­contrast/

This site provides a Colour Palette Accessibility Evaluator

achecker.ca/checker/

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

mozilla.org/en-­Us/firefox/addon/fangs-­screen-­reader-­emulator

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

jigsaw.w3.org/css-­validator

This website checks an entire website and evaluates its conformance with W3C open standards to quickly identify those portions of the website that need attention

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