Cognomen Molby (Molby 
) , across the world, is a rare last name. The last name Molby is characteristic of Denmark, where it is a rare surname, the United States, where it is a very rare surname, and Canada. Very seldom, Molby is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Molby | Canada, India, United States, United Kingdom, Denmark |
| ethel enola molby American botanical collector (1904 – 2003), US (b. 1904) |
|