Web-browsers use the URL protocol prefix (http://) to determine the port number (http = 80, https = 443, ftp = 21, etc.) unless the port number is specifically typed in the URL (for example “http://www.simpledns.com:5000” = port 5000).
Read moreWhat is URL port?
Use in URLs Port numbers are sometimes seen in web or other uniform resource locators (URLs). By default, HTTP uses port 80 and HTTPS uses port 443 , but a URL like http://www.example.com:8080/path/ specifies that the web browser connects instead to port 8080 of the HTTP server.
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