Technology & Units
What Is URL Encoding?
URL encoding (percent-encoding) replaces unsafe characters in web addresses with a % followed by their hexadecimal code, like %20 for a space.
URLs may only contain a limited set of characters, so anything else — spaces, accented letters, symbols like & or ? used literally — must be percent-encoded: replaced by % plus the character’s hexadecimal byte value. A space becomes %20, an ampersand %26.
Encoding prevents ambiguity between characters that have structural meaning in a URL and the same characters appearing inside data, such as a search query. Every programming language provides encode/decode functions, and browsers do it automatically in the address bar.