Last name แก้วจรรยา (Glass 
, แก้วจรรยา) , globally, is a common cognomen. The cognomen แก้วจรรยา is habitual in Guernsey, where it is quite a common surname, New Zealand, and the United States. In absolute terms, it is commonest in the United States, the United Kingdom, and Germany. Very seldom, แก้วจรรยา is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Glass | Germany, Australia, Canada, United States, United Kingdom |