What is the standard seat width for office chairs?

Standard commercial office chairs have a seat width of 17"–20", with 18"–19" being the most common. Big-and-tall chairs have wider seats at 20"–24". Seat width should leave 1"–2" of clearance on each side between hips and seat edges. At OfficeFurniture2go.com, all chair specs include seat width dimensions — call 1-800-460-0858 if you need help matching a chair to a specific user's measurements.