刻托（Κητος / Ceto，“海怪”）是希腊神话中的一个凶恶的海怪，盖娅和蓬托斯的女儿。

她是叵测的大海给人带来的危险的化身，也是未知的陆地以及诡异生物的象征。在希腊语中，“刻托”一词最终被用来代表所有的海怪，直到今天。她的丈夫是福耳库斯，他们拥有众多的孩子，统称为“福耳库德斯”（Phorcydes）。

在希腊艺术中她被表现为半蛇半鱼，鲸鱼座（Cetus）来源于她。

For the minor planet, see 65489 Ceto.

Ceto or Keto (Ancient Greek: Κητώ, Kētō, "sea monster"), is a primordial sea goddess in Greek mythology, the daughter of Gaia and Pontus. Ceto was also variously called Crataeis (Κράταιις, Krataiis, from κραταιίς "mighty") and Trienus (Τρίενος, Trienos, from τρίενος "within three years"), and was occasionally conflated by scholars with the goddess Hecate (for whom Trienus and Crataeis are also epithets). As a mythological figure, she is most notable for bearing by Phorcys a host of monstrous children. The small solar system body 65489 Ceto was named after her, and its satellite after Phorcys.