In Egyptian art Ptah was often portrayed as a bearded, bald male figure who wore a tight cap and an elaborately decorated neckcollar, and whose body was wrapped in a tight garment that left only his hands free. The menat, the symbol of pleasure and happiness, hung down the back of his neck. He sat or stood on a pedestal symbolic of Ma'at, who represented Truth, and held in his hands the ankh, a symbol of life, and the scepter, a symbol of power. Sometimes he was shown at his potter's wheel. The hieroglyphs that represented his name included the meanings “to open,” “to engrave,” “to carve,” and “to chisel.” The name Ptah itself may have meant “sculptor” or “engraver.”

Ptah's chief attribute was his power to give form to everything, and he was called the Architect of the Universe. He shaped the gods, the cities, the nomes, or provinces, of Egypt, and all things of beauty. According to one text, Ptah was the father of Atum, who later became the sun-god Ra. The Egyptians believed that Ra would originate thoughts. Then the god of intelligence, Thoth, would give words to Ra's thoughts. But it was Ptah who gave these thoughts form. Ptah was assisted by Ma'at, goddess of truth and justice, and by the god Khnemu, who shaped humans on his own potter's wheel. Ptah was a creative force even in death, for he would shape new bodies for the souls of the deceased to inhabit in the Duat (Underworld).

Ptah was often associated with or even fused with other gods, particularly with Osiris and with Sekar (also spelled Soker). Ptah was thought to have existed at the beginning of time within Nu, the primeval watery chaos, and Ptah created the world from that chaos either by kneading mud or through speech. Ptah was identified in some way with the Apis bull, which was also worshiped in Memphis. This bull was thought to be the incarnation of Ptah during its life, but when it died, it assumed the identity of the god Osiris and was called Serapis. Ptah was also thought to have absorbed the qualities of a predynastic god named Tenen, and this combined form was usually depicted as a human male with a crown of ostrich feathers, holding a scimitar. Occasionally Ptah was shown with the Seven Wise Ones, beings who came from Ra's tears and took the form of hawks. The Seven Wise Ones, along with Thoth in his role as scribe, ruled over letters and learning. In these scenarios, Ptah was the force carrying out the dictates of these deities, giving form to their designs.

After the heresy of Akhenaton was denounced and Tutankhamen had restored the traditional religion, it was declared that all gods were in essence three gods: Amen, Ra, and Ptah. During the Ramesside era, Ptah was still highly regarded; so much so that the fourth son of Ramses the Great, Khaemwese, was famous as the high priest of Ptah at Memphis.

The Greeks identified Ptah with their god Hephaestus, and the Romans identified him with Vulcan.