URL()

The URL() constructor returns a newly created URL object representing the URL defined by the parameters.

If the given base URL or the resulting URL are not valid URLs, the JavaScript TypeError exception is thrown.

Syntax

const url = new URL(url [, base])

Parameters

url

A USVString representing an absolute or relative URL. If url is a relative URL, base is required, and will be used as the base URL. If url is an absolute URL, a given base will be ignored.

base Optional

A USVString representing the base URL to use in cases where url is a relative URL. If not specified, it defaults to undefined.

Exceptions

Examples

// Base urls
let m = 'https://developer.mozilla.org';
let a = new URL("/", m);                                // => 'https://developer.mozilla.org/'
let b = new URL(m);                                     // => 'https://developer.mozilla.org/'

        new URL('en-US/docs', b);                      // => 'https://developer.mozilla.org/en-US/docs'
let d = new URL('/en-US/docs', b);                     // => 'https://developer.mozilla.org/en-US/docs'
        new URL('/en-US/docs', d);                     // => 'https://developer.mozilla.org/en-US/docs'
        new URL('/en-US/docs', a);                     // => 'https://developer.mozilla.org/en-US/docs'
        
        new URL('/en-US/docs', "https://developer.mozilla.org/fr-FR/toto");
                                                       // => 'https://developer.mozilla.org/en-US/docs'
                                                       
        new URL('/en-US/docs', '');                    // Raises a TypeError exception as '' is not a valid URL
        new URL('/en-US/docs');                        // Raises a TypeError exception as '/en-US/docs' is not a valid URL
        new URL('http://www.example.com', );           // => 'http://www.example.com/'
        new URL('http://www.example.com', b);          // => 'http://www.example.com/'

        new URL("//foo.com", "https://example.com")    // => 'https://foo.com' (see relative URLs)

Specification

Browser compatibility

See also

• The interface it belongs to: URL.