Web browsers will take the IRI (Internationalised Resource Identifier; think of it as a URI but containing non-ascii characters), and turn it into a URI (contai

Web browsers will take the IRI (Internationalised Resource Identifier; think of it as a URI but containing non-ascii characters), and turn it into a URI (containing a load of percent-encoded utf-8 bytes instead of non-ascii characters) and send that to the web server. So your website will need to decode the percent-encoded utf-8 bytes into Unicode characters. (On phone, simplifying a bit. I encourage you to read the relevant RFC.)