What was Superman's first name?

Answer 1

Superman's "mother" and "father" on Krypton named him Kal-El.

It was only after he arrived on planet Earth that he got the name "Clark Kent" and "Superman".

In some versions he became "Superboy" before he became "Superman" for obvious reasons.

Answer 2

Superman's first name is Clark. His full name is Clark Kent.

Answer 3

His real name, which was given to him by his parents on the planet Krypton is:

KAL-EL

Answer 4

Kal-El