Kepler-1664 is a Sun-like G-type star (about 0.94 solar masses, 5,736 K), 627 light-years from Earth. Kepler-1664 b is a planet with 3.0 Earth radii, with an orbital period of 14.4 days, discovered in 2020 via transit. The planet was found when it crossed the face of its star, producing periodic dips in brightness that reveal its size and orbital period to space-based photometry. At roughly 627 light-years, Kepler-1664 lies far beyond the nearest stars yet remains reachable to large survey telescopes. Repeated transit observations constrain the planet's orbital inclination and stellar density, anchoring the system's physical scale.