Checks Accessibility, HTML, CSS, Links, and Spelling

Browser extensions

These are free to use, but please read the licence before downloading them.

They are all fully tested on Windows, macOS and Linux, but they need Total Validator Test, Basic or Pro to be installed.

Display this page using the appropriate browser, and then click the corresponding button below to start the installation.

* Firefox users upgrading from v5.1 please note that a recent change to Firefox may cause the TV icon to disappear from your toolbar or the Context Menu. If this happens then remove the Total Validator add-on, restart your browser and add it back again.

Documentation: Chrome, Firefox, and Edge
Recent changes: Change log