TOI-2084 is a cool M-dwarf (about 0.45 solar masses, 3,551 K, 0.47 solar radii), 115 light-years from Earth. TOI-2084 b is a planet with 2.5 Earth radii, with an orbital period of 6.1 days, at 0.050 AU from its star, and an equilibrium temperature near 527 K, discovered in 2023 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. TOI-2084 b orbits well inside Earth's distance from the Sun.