140.25 Hz is the planetary frequency of Pluto, calculated from its orbital period using the cosmic octave method. Although Pluto was reclassified from planet to dwarf planet in 2006, its symbolic and energetic significance remains central to many sound healing and astrological traditions.

Pluto has always been associated with the forces of transformation — death and rebirth, the destruction of old forms to make way for new ones. In mythology, Pluto rules the underworld, and in astrology it governs the processes of deep psychological change, power dynamics, and regeneration.

Sound therapists use 140.25 Hz when working with transitions, grief, and the need to release what no longer serves. The frequency is considered particularly useful during periods of major life change — endings, new chapters, or any moment that requires letting go of the familiar in order to grow.