| Name | Gender | Pronounced | Usage | Popularity |
|---|---|---|---|---|
| OTTÓ | - | Hungarian, Icelandic | ||
| OTTAVIA | - | Italian | ||
| OTTAVIANO | - | Italian | ||
| OTTAVIO | - | Italian | ||
| OTTILIA | oot-TEE-lee-ah | Swedish | ||
| OTTILIE | o-TEE-lee-ə | German | ||
| OTTMAR | - | German | ||
| Otto | ['ɔtəu] | |||
| OTTO | AW-to (German), AH-to (English), OT-to (Finnish) | German, Swedish, Norwegian, Danish, Dutch, English, Finnish, Ancient Germanic | ||
| OTTOKAR | - | German | ||
| OTTOLINE | - | English (Rare) | ||
| OTTOMAR | - | German | ||
| OTTONE | - | Italian | ||
| OTTORINO | - | Italian | ||
| OTYLIA | - | Polish |