Surname Kalwan (Kalwan 
) , globally, is a rare last name. The cognomen Kalwan is habitual in Bahrain, where it is quite a rare surname, Tanzania, where it is a rare surname, and Indonesia, where it is a very rare surname. Measured by absolute frequency, it is commonest in Tanzania, Indonesia, and India. Also, Kalwan is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Kalwan | Indonesia, Tanzania, India, Bahrain, Brazil |