Seat height determines the position of the user's knees, thighs and feet relative to the floor and workstation. An appropriate seat height generally allows the user's feet to rest comfortably while maintaining a suitable relationship between the seat and desk.
Adjustable seat height is particularly useful in ergonomic office chairs because users differ significantly in height and leg length. It also allows the chair to be adjusted to different desk heights.
Seat height is normally measured from the floor to the upper surface of the seat, although the exact measurement method can vary depending on the chair design and whether the seat is compressed.