How many Titans were there according to Hesiod?

According to Hesiod, there were twelve Titans.

In the Theogony, Hesiod lists the twelve children of Uranus, the sky, and Gaia, the earth. The six male Titans are Oceanus, Coeus, Crius, Hyperion, Iapetus, and Cronus; the six Titanesses are Theia, Rhea, Themis, Mnemosyne, Phoebe, and Tethys.

These Titans belong to the generation of gods before the Olympians. Cronus later overthrew Uranus, but Zeus and his siblings eventually defeated Cronus and the Titans in the Titanomachy, a ten-year divine war. Hesiod distinguishes the twelve Titans from the three Cyclopes and three Hundred-Handers, who are also children of Uranus and Gaia.

Later writers sometimes called other descendants of the Titans—such as Atlas, Prometheus, Helios, and Leto—“Titans” as well. That broader usage can cause confusion, but when the question asks specifically for Hesiod’s original group, the canonical number is twelve.