Surname 昌曰 (昌曰 
) , in the entire world, is a very rare cognomen. The cognomen 昌曰 is habitual in Eastern Asia, particularly China, where it is an extremely rare surname. More frequently, 昌曰 is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| 昌曰 | China |