URL Decoder

Recall that URLs are sent to the Internet by browsers in ASCII encoding. If any URL contains characters that are not in ASCII encoding, the URL is automatically converted by the browser. URL conversion refers to replacing unsafe characters with a% followed by two hexadecimal numbers that match the ISO-8859-1 character values. Any sequence of the form %xy is considered a byte, where xy is a two-digit hexadecimal representation of 8 bits. All substrings that have one or more sequences are replaced with a character or characters whose encoding will result in sequential bytes. The URL contains a limited set of US-ASCII characters, including alphabet (A-Z a-z), numbers (0-9), dash (-), underscore (_), tilde (~), and period (.). Any other character outside the valid set is encoded using URL encoding or percentage encoding.

Of course, users can decode them on their own (for example, by clicking on the address line, adding any sign, removing it, and only then copying the address), but this is inconvenient. Sometimes you need to decode the url string into human readable text. You can, of course, replace all% 20 with spaces, and assume that the problem is solved. But what if not only spaces are encoded in the same way? If you come across a URL with a bunch of similar percentages at the entrance? Some characters cannot be part of the URL (for example, a space), and some other characters have special meaning in the URL: for example, the # character can be used to further indicate a subsection (or portion) of a document. In HTML forms, the = character is used to separate name from value. The generic URI syntax uses URL encoding to solve this problem, while HTML forms do some additional substitutions rather than applying percentage encoding to all such characters.