Knobs range in style from round, square, oblong, octagonal, etc. Knobs that are 1 inch or smaller are generally good for specialized pullouts such as spice drawers and cutting boards. Knobs that are 1 ¼” to 1 ⅜” are standard for most applications. Any knob that is 1 ½ inches or larger is generally used on larger cabinets or if someone is really trying to make their hardware stand out and look more dramatic.