Surname สมการ (สมการ 
, Samakan 
) , around the world, is a rare cognomen. The surname สมการ is habitual in South-eastern Asia, particularly Thailand, where it is a rare surname, Indonesia, where it is a very rare surname, and Philippines. Likewise, สมการ is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| สมการ | Thailand |
| Samakan | Indonesia, Malaysia, Philippines, Thailand, India |