No, Loki is not a Frost Giant in Norse mythology, although he does have ties to the Frost Giants.
Loki is actually the son of the giant Farbauti and the goddess Laufey, making him part giant in heritage. While he is often associated with the Frost Giants, who are also known as the Jotnar, he is more commonly depicted as a trickster god in the pantheon of Asgard, associated with mischief and chaos.
Loki’s complex character is a blend of both divine and giant traits, which allows him to traverse between the realms of gods and giants. Throughout the myths, he often aids the gods like Odin and Thor but also causes trouble for them. His relationship with the Frost Giants adds depth to his character, showcasing his ability to navigate multiple worlds and allegiances.