Surname Арнолди (Arnoldi 
, Арнолди 
) , around the globe, is quite a common cognomen. The last name Арнолди is characteristic of Italy, where it is quite a rare surname, Denmark, and Switzerland. In absolute terms, it is commonest in Italy, Indonesia, and Germany. Very seldom, Арнолди is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Arnoldi | France, United States, Germany, Indonesia, Italy |
| Арнолди | Russia, Armenia |