Useful if you have access to the source code of the page. You can test one web page anonymously or you can create an account that allows you to test up to 25 web pages as well as the option to archive the test results for future review. Note that this tool reflects Illinois state law and UIUC guidelines.
A free screen reader application for Windows computer. It's not as comprehensive as JAWS screen reader software, but it's quite comparable. Donation is encouraged so the developer can keep it up to date.
Formerly known as "Firefox Accessibility Extension" this is a free, open source based tool to evaluate web pages for WCGA 2.0. compliance using the HTML5 and ARIA standards. You can also find find the AInspector Sidebar on the Mozilla Add-on site.
This is a useful tool if you work on developing a website. While they don't include accessibility assessment as part of the tools, the Responsive Design Mode tool is especially useful to help you see how the website would look like on different devices such as tablets and phones.
Developed by Deque, the tool offers a couple of approaches: install it as a bookmarklet or using their web form to test part of a web page. The source code of the boomarklet is provided. Note: this tool does not check the raw HTML.
Developed by Khan Academy, tota11y is an accessibility visualization toolkit that helps visualize how a web page performs with assistive technologies. Included in the toolkit is an experimental option to see how a page will be viewed as a screen reader would.