Family name Gnanaratnam (Gnanaratnam 
) , globally, is a rare cognomen. The family name Gnanaratnam is characteristic of Sri Lanka, where it is quite a rare surname, Australia, where it is a very rare surname, and Canada. In absolute terms, it is the most numerous in Sri Lanka, Canada, and the United Kingdom. Much less frequently, Gnanaratnam is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Gnanaratnam | Australia, Canada, United Kingdom, India, Sri Lanka |