KMT-2021-BLG-1303L is a Sun-like G-type star (about 0.57 solar masses, 5,778 K), 6,280 light-years from Earth. KMT-2021-BLG-1303L b is a 0.38-Jupiter-mass companion, at 2.890 AU from its star, discovered in 2022 via microlensing. Microlensing detections occur when a foreground star's gravity briefly magnifies a background source, revealing planets that are otherwise too faint and distant to observe directly. KMT-2021-BLG-1303L b circles in the outer system, comparable to the Jupiter region. At roughly 6,280 light-years, KMT-2021-BLG-1303L lies far beyond the nearest stars yet remains reachable to large survey telescopes.