| EQUIVALENTS |
| ANCIENT GERMANIC: Wilhelm, Willahelm |
| BRETON: Gwilherm |
| CATALAN: Guillem |
| CROATIAN: Vilim |
| CZECH: Vilém |
| DANISH: Vilhelm |
| DUTCH: Wilhelmus, Willem |
| ESPERANTO: Vilhelmo |
| ESTONIAN: Villem |
| FINNISH: Vilhelm, Vilhelmi, Viljami |
| FRENCH: Guillaume |
| GERMAN: Wilhelm |
| HUNGARIAN: Vilhelm, Vilmos |
| ICELANDIC: Vilhjálmur |
| IRISH: Uilliam |
| ITALIAN: Guglielmo |
| LATVIAN: Vilhelms |
| LIMBURGISH: Wöllem, Wullem |
| LITHUANIAN: Vilhelmas |
| MANX: Illiam |
| MAORI: Wiremu |
| NORWEGIAN: Vilhelm |
| POLISH: Wilhelm |
| PORTUGUESE: Guilherme |
| SCOTTISH: Uilleam |
| SLOVAK: Viliam |
| SLOVENE: Viljem |
| SPANISH: Guillermo |
| SWEDISH: Vilhelm |
| WELSH: Gwilim, Gwillym, Gwilym |
|
| DIMINUTIVES AND SHORT FORMS |
| CROATIAN: Vilko |
| DUTCH: Jelle, Pim, Wil, Willy, Wim |
| ENGLISH: Bill, Billie, Billy, Liam, Wil, Will, Willie, Willy |
| ESPERANTO: Vilĉjo |
| FINNISH: Jami, Vilho, Vili, Viljo, Ville |
| GERMAN: Willi, Willy, Wim |
| HUNGARIAN: Vili |
| IRISH: Liam, Uilleag, Ulick |
| LATVIAN: Vilis |
| LIMBURGISH: Wum |
| MEDIEVAL ENGLISH: Wilkin, Wilky, Wilmot |
| SLOVENE: Vili, Vilko |
| SWEDISH: Ville |
| WELSH: Gwil |
|
| FEMININE FORMS |
| CROATIAN: Vilma |
| CZECH: Vilma |
| DUTCH: Elma, Helma, Mien, Mina, Wil, Wilhelmina, Willemijn, Willemina, Willy, Wilma |
| ENGLISH: Mina, Minnie, Velma, Wilhelmina, Willa, Wilma |
| FINNISH: Helmi, Iina, Miina, Mimmi, Minna, Vilhelmiina, Vilma |
| GERMAN: Elma, Helma, Helmine, Minna, Vilma, Wilhelmina, Wilhelmine, Wilma |
| HUNGARIAN: Vilma |
| LIMBURGISH: Mien, Mina |
| LITHUANIAN: Vilhelmina |
| POLISH: Wilhelmina |
| SLOVAK: Vilma |
| SPANISH: Vilma |
| SWEDISH: Helmi, Mimmi, Minna, Vilhelmina, Vilma |
|
| OTHER FORMS |
| ENGLISH: Liam, Wilkie, Willis, Wilson |
|