What planet are the Transformers originally from?

The Transformers are originally from the planet Cybertron.

Cybertron is the metallic homeworld of the Transformers, including both the heroic Autobots and their enemies, the Decepticons. It is usually portrayed as a vast mechanical world covered with cities, industrial structures, energy systems, and ancient technology rather than natural landscapes familiar from Earth.

Many Transformers stories connect Cybertron’s creation to Primus, a god-like being who becomes—or is closely associated with—the planet. The world’s life force is represented differently across continuities, with concepts such as the AllSpark, the Well of AllSparks, and Vector Sigma playing important roles in the creation or animation of Transformers.

The planet’s capital is commonly identified as Iacon. Cybertron is not merely a setting: its civil war, resource shortages, political divisions, and struggle between Autobot and Decepticon ideologies provide the central background for the franchise. Some stories move the conflict to Earth or other worlds, but those locations are destinations or battlefronts, not the Transformers’ original homeworld.