Family name Forsth (Forsth 
) , all around the world, is a very rare last name. The family name Forsth is characteristic of Norway, where it is a rare surname, the United Kingdom, where it is an extremely rare surname, and Canada. Much less frequently, Forsth is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Forsth | United Kingdom, Norway, Brazil, Canada, United States |