Can I test my development and test websites, or do they need to be publicly accessible?

Both our interactive live tests and the automated screenshot tests can work with your internal development and test web servers, even if they are behind a protective firewall. To do this, modify your firewall to allow incoming http (and https if needed) requests from 216.37.72.238 (crossbrowsertesting.com). Incoming connections should be directed to a particular internal dev or test server. You can filter on CrossBrowserTesting's ip address so only traffic from our testing service can access these internal web servers. This works with both our screenshot system and the live testing. The configuration changes to the firewall are pretty trivial.