All .onion websites on the Dark Web are now shifted towards the Onion v3 protocol. That means many of the existing Dark Web Websites will no longer be accessible unless you know their new v3 .onion address. To see if the .Onion URL you’re trying to access is v2 or v3, the most telling sign is the length of the URL. v3 .onion addresses are 56 characters in length. The older v2 URLs are only 16 characters in length.