🕯 lampshade Lamp Size Calculator
Match shade width, height, and clearance to your lamp
| Table width | Ideal full lamp height | Shade width | Base diameter |
|---|---|---|---|
| 12-16 in / 30-41 cm | 20-24 in / 51-61 cm | 8-10 in / 20-25 cm | 4-6 in / 10-15 cm |
| 18-22 in / 46-56 cm | 22-28 in / 56-71 cm | 10-14 in / 25-36 cm | 5-7 in / 13-18 cm |
| 24-28 in / 61-71 cm | 24-30 in / 61-76 cm | 12-16 in / 30-41 cm | 6-9 in / 15-23 cm |
| 30-36 in / 76-91 cm | 26-32 in / 66-81 cm | 14-18 in / 36-46 cm | 7-10 in / 18-25 cm |
| Use profile | Eye gap | Height bias | Best match |
|---|---|---|---|
| Task lighting | 24-28 in | 1.00 | Clear task light |
| Soft ambient glow | 22-26 in | 0.96 | Relaxed table use |
| Room-filling balance | 24-29 in | 1.02 | Balanced twin lamps |
| Tall lamp balance | 26-30 in | 1.06 | Raised visual line |
| Base diameter | Footprint area | Approx top use | Best for |
|---|---|---|---|
| 4 in / 10.2 cm | 12.6 sq in | 5% | Mini lamp |
| 5 in / 12.7 cm | 19.6 sq in | 8% | Compact table |
| 6 in / 15.2 cm | 28.3 sq in | 11% | Balanced style |
| 7 in / 17.8 cm | 38.5 sq in | 15% | Heavier lamp |
| Inches | Centimeters | What it means | Notes |
|---|---|---|---|
| 12 | 30.5 | Small shade | Compact table |
| 16 | 40.6 | Wide shade | Bold table look |
| 20 | 50.8 | Tall lamp | Good over low stands |
| 24 | 61.0 | Lampshade height | Common support line |
Picking a lampshade is like finding a good hat. Too big or too small it can seem a bit odd. The secret is to match the size of the shade to the base of the lamp.
When the proportions match, the look becomes nice and enjoyable.
How to Pick the Right Lampshade Size
Choosing a lampshade is not always simple. Take a tape measure and notebook to start. Consider the height, width and proportions of the shade.
If you replace an old one and it pleases you, simply measure it with a ruler or retractable tapemesuire.
Lampshade sizes are shown by the bottom diameter, usually in even numbers, using the format Top x Bottom x Slant. They are listed by the diameter of the base, which is the widest part. That is the main size of the shade.
Before measuring, remove the shade from the lamp. Lay it on a table. If the lamp has a clip for the shade, it easily pulls off the bulb.
There are some useful rules. The shade should be around 40% of the whole height of the lamp and double the size of the lamp base. Most seriously, it must cover the socket.
For a 6-inch lamp base, use at least a 12-inch width for the shade. And if the lamp height with bulb and harp is 24 inches, the shade should be 8 inches tall.
Another way: height of the shade matches around two thirds of the lamp base height. For a small or slim base, the diameter of the shade matches the height of the base. A 35cm high lamp base ideally matches with a 35cm diameter shade, plus or minus 2-5cm.
Practical rule of thumb: take the widest part of the lamp, multiply by 1.75 and round to the nearest inch. That commonly gives a great result. The bottom edge of the shade always stays under the sowket and above the top of the lamp body.
Occasionally the harp also needs a change.
Occasionally the lampshade is not wrong in size, it is simply too high up. Also the position matters. The right size can seem too big if the lamp stands wrong.
Then a smaller, vintage lamp with a fabric shield will work better. Room size or distance to the ceiling also affects the light quality.
Lampshades come in metal, fabric, paper, rattan and glass, in many sizes. A store specialized in shades helps with advice about size, shape and styles. The size depends also on the harp inside the lamp.
Custommade shields are a good option to consider.
