Seat height refers to the vertical distance from the seat surface to the ground; If the seat surface is backward inclined or concave arc, the seat height refers to the vertical distance from the center point of the seat front to the ground. If the seat is too high, the legs will be suspended and the blood vessels of the thigh will be compressed; Too low can cause physical fatigue. Practice has proved that the appropriate seat height is the height from calf socket to sole plus 25-35mm heel thickness, minus 10-20mm movement allowance. Namely:

Seat height h = calf socket height + heel thickness - appropriate gap

According to the national standard GB 3326-1997, the seat height h is 400-440mm and the dimension difference is 10mm. The maximum height of soft seat surface is 460mm (excluding seat surface subsidence). Sofa seat height can be lower, so that the leg forward, leaning back, conducive to the spine in a natural state. The seat height of sofa is generally 360-420mm.