A RFC 3986 requer codificação percentual de caracteres Unicode em URLs:
When a new URI scheme defines a component that represents textual data consisting of characters from the Universal Character Set, the data should first be encoded as octets according to the UTF-8 character encoding; then only those octets that do not correspond to characters in the unreserved set should be percent-encoded. For example, the character A would be represented as
A
, the character LATIN CAPITAL LETTER A WITH GRAVE would be represented as%C3%80
, and the character KATAKANA LETTER A would be represented as%E3%82%A2
.
Embora isso se aplique a novos esquemas de URI, a maioria dos navegadores atuais executará a codificação percentual em URLs.