12 Pegasi is a K-type supergiant star in the northern constellation of Pegasus. It is faintly visible to the naked eye with an apparent visual magnitude of +5.3. Based on parallax measurements, it is located at a distance of approximately from the Earth. The star is drifting closer with a line of sight velocity component of −10.1 km/s.
This evolved star has a spectral type of K0Ib Hdel0.5, which indicates that it is a less luminous K-type supergiant with strong H-δ Balmer lines. It is an estimated 20 million years old and is spinning with a projected rotational velocity of 19.5 km/s. With 6.3 times the mass of the Sun, it has expanded to 81 times the radius of the Sun. The star is radiating 1,722–1,820 times the luminosity of the Sun from its photosphere at an effective temperature of 4,185 K.
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