The authors agree that the surname derives from Latin forms related to Gratius / Gratia. E. Rossoni notes that the surname comes from the Latin cognomen Gratius, and that Grazi is typical of the area between Emilia-Romagna and Tuscany, with a presence in the Modena, Bologna, Ferrara, Florence, Grosseto, Siena and Arezzo areas. He adds that the variant Grazio, rarer, would appear to be specific to the Verona area.

F. De Laurentiis broadens the picture and indicates that the surname is found throughout Italy with varying frequency, and that its base lies in the names Grazia, Grazio, Grazioso and Graziano. He notes that the Romans already used the feminine name Gratia(m), derived from Grata(m), with an origin of a religious character: "pleasing (to the gods)". He adds that the late popularity of these forms in Italy may be linked in part to the influence of the English equivalent Grace, widespread especially among the Puritans after the Reformation.