A DC-to-DC converter includes a first switching circuit, a second switching circuit, a transformer positioned between an AC side of the first switching circuit and an AC side of the second switching circuit, an inductance element positioned between the transformer and at least one of the AC side of the first switching circuit and the AC side of the second switching circuit, and control circuitry that operates the first switching circuit and the second switching circuit. The control circuitry sets a predetermined operation ratio of the first switching circuit and the second switching circuit to each other, and adjusts, based on the predetermined operation ratio, a first operation period of the first switching circuit and a second operation period of the second switching circuit.