Family name קליי (Clay 
, Kley 
, Klej 
) , all over the world, is a common last name. The surname קליי is habitual in Isle of Man, where it is quite a common surname, the United States, and the United Kingdom, where it is quite a rare surname. Measured by absolute frequency, it is the most numerous in the United States, the United Kingdom, and Germany. Likewise, קליי is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Clay | Germany, Australia, Indonesia, United States, United Kingdom |
| Kley | Germany, Australia, Democratic Republic of the Congo, United States, United Kingdom |
| Klej | Germany, Canada, Philippines, United Kingdom, Poland |
| קליי | Israel |