BlockIt

BlockIt is a useful browser extension that allows you to restrict the access to certain websites when using Google Chrome. The extension can be used to prevent users from accessing dangerous websites or the ones that include inappropriate content.
You can use this tool to filter the websites accessible to your children or other computer users. Unlike other extensions, this tool does not have a predefined set of websites and allows you to create your own list of restricted domains.
You have the option of defining the available websites in two different ways. The first method allows you to enter the websites that you want to block and is recommended when the user requires access to multiple websites.
The second method is suitable when you need to block all websites except some that are used by the user. This method requires a much smaller list of websites and it is suitable for working environments that require tighter security restrictions.
When a webpage is blocked, the browser loads a standard page with a warning message. The warning message can be customized by using HTML tags in order to email address or a link to the helpdesk page. This enables the users to report any problems or to request website access.
The Options window includes the possibility to create a password for preventing unauthorized access. Unfortunately, the feature is not active and there is no way to prevent other users to change the settings and the blocked sites list.
BlockIt allows you to filter the web content that can be accessed by other Google Chrome users. However, you should be aware that without the password protection most users can easily change its settings.