URL.prototype.port

The port number of the URL.

Example

let url = new URL("https://example.com:8080/path")
url.port

"8080"

let url = new URL("https://example.com/path")
url.port

""

let url = new URL("https://example.com")
url.port = "3000"
url.href

"https://example.com:3000"