20 mm Knobs for Smaller Pieces
Smaller knobs often work best on jewelry boxes, makeup organizers, and compact storage furniture where a delicate look makes sense.
30 mm Knobs for Standard Drawers
A 30 mm knob is often a flexible middle size for dressers, cabinet doors, and nightstands. It offers enough visibility without feeling too bold.
40 mm Knobs for Larger Furniture
Larger knobs can make a stronger design statement and may be better suited for wide dresser drawers, larger cupboards, or furniture where you want the hardware to stand out.
Consider the Furniture Front
The drawer or door size should guide the choice. Hardware should look intentional and balanced in relation to the panel it is attached to.
Conclusion
The best knob size depends on both function and scale. Matching the knob size to the furniture front helps the finished project look more polished.