decodeURI()

The decodeURI() function decodes a Uniform Resource Identifier (URI) previously created by encodeURI() or a similar routine.

decodeURI() is a function property of the global object.

The decodeURI() function decodes the URI by treating each escape sequence in the form %XX as one UTF-8 code unit (one byte). In UTF-8, the number of leading 1 bits in the first byte, which may be 0 (for 1-byte ASCII characters), 2, 3, or 4, indicates the number of bytes in the character. So by reading the first escape sequence, decodeURI() can determine how many more escape sequences to consume. If decodeURI() fails to find the expected number of sequences, or if the escape sequences don’t encode a valid UTF-8 character, a URIError is thrown.

Syntax example: decodeURI(encodedURI)