Cognomen Charnsak (Charnsak 
) , all around the world, is an extremely rare surname. Much more frequently, Charnsak is the forename as well as the last name.
Sermkarndee, Mongkolboreruk, Treethepvilai, Thongsornkleeb, Laoruangroj, Suraprasert, Taechawiwat, Luangtriratana, Sinthucharoen, Udomtiraphan, Pholharn, Kurkcharoen, Songpiriyakij, Senachai, Sukajintanakarn, Sangsubin, Maspakorn, Leenasiri, and Srisawatsakul