Adjusting device for a headrest of a vehicle seat and vehicle seat

The present disclosure relates to an adjusting device for a headrest of a vehicle seat, the adjusting device comprising: a backrest fastening for attaching to a backrest, a holding device with a vertical adjustment means for adjusting the headrest in vertical direction, a longitudinal adjusting means for adjusting the holding device in a longitudinal direction, the longitudinal adjusting means comprising a four-joint gear provided between the backrest fastening and the holding device, the four-joint gear comprising two guiding arms. Here, the longitudinal adjusting means comprises a spindle drive, the spindle drive being provided between the holding device and one of the guiding arms. The guiding arm is preferably a front guiding arm. A spindle of the spindle drive is preferably translationally displaceable and provided in an arc-shaped slot guiding of the guiding arm. Moreover, a vertical adjustment by a second spindle drive is provided.