How to write William in Japanese
In Japan, William is written in katakana: ウィリアム, pronounced “wiriamu”. That's the spelling to use on a form, a name tag, or when you introduce yourself.
The kanji above are ateji — characters picked because they sound like the name. There's no single official version, so go with the one whose meaning you like best.
William in kanji, character by character
More names in Japanese
Kanji meanings from KANJIDIC2 © EDRDG (CC BY-SA 4.0).