Proportion Shade to a Lamp. Set shade next to base. It should be the same height as the lamp base or 2" shorter, depending on aesthetic. Measure circumference of the bottom of lamp shade. It should be at least twice the circumference of the lamp, but not more than 2 1/2". Check how much of the neck of the lamp beneath the socket is showing once you've place the shade on the lamp. About a 1/2 inch of neck should be visible. Include any length that's added by fringe or other decoration.
LAMPSHADE LESSON: The height of the shade itself should make up one-third to one-half the total height of the lamp. Use the lamp's total height measurement to get the appropriate proportions for the width. The width, measured at the bottom of the lampshade, should fall between one-half to three-quarters the height of the lamp.
how to choose a shade. should be 2/3 of lamp height of base. 1/2 inch over the widest part. rd base need rd lamp