The Netcraft Extension is a free tool to help you browse the web safely, and to protect you from the potential harms of web browsing.

You can use it to easily view the IP address of the websites you visit, check to see if the site is safe to visit, and even get useful information like the estimated traffic volume and estimated server load.

There is also a built-in search engine that you can search for URLs, domains, email addresses and IP addresses.

To add an URL to the Netcraft search, you can copy the URL and use the "URL" field.