How to Choose the Right Lampshade Size: Simple Rules
The right lampshade size depends on your lamp base. As a simple rule, the shade should be about twice as wide as the base and around two-thirds of the height of the base. It should also hide the bulb and fitting when you look at it from a normal standing or seated position, and match the type of fitting on your lamp.
This guide explains how to measure your lamp, the easy sizing rules for table lamps, floor lamps and ceiling shades, how to choose the right shape and fitting, and the most common mistakes to avoid.
The Short Answer
- Width: the shade’s bottom diameter should be about twice the width of the lamp base at its widest point.
- Height: the shade should be about two-thirds of the height of the base, measured from the bottom of the base to the bulb holder.
- Coverage: the shade should hide the bulb holder and the metal fitting.
- Fitting: make sure the shade matches your lamp fitting, such as a standard UK duplex fitting.
- Safety: check the maximum wattage and use LED bulbs, which stay cooler.
How to Measure Your Lamp
You only need a tape measure. Take these three measurements before you shop:
- Base width: measure the widest part of the lamp base from side to side.
- Base height: measure from the bottom of the base to the bottom of the bulb holder. Do not include the bulb.
- Fitting type: check whether the shade sits on the bulb holder, on a harp (a metal frame around the bulb), or hangs from a ceiling pendant.
Lampshade Size Rules for Table Lamps
Width
The bottom of the shade should be roughly twice the width of the base. For example, a base that is 15 cm wide suits a shade about 30 cm across. The shade should be at least 2.5 cm wider than the base on each side, so the lamp does not look top-heavy or squashed.
Height
The shade should be around two-thirds of the height of the base. A base that is 36 cm tall usually suits a shade about 24 cm tall. Together, the base and shade should look balanced, with the shade not hiding most of the base.
Eye level
When you sit next to a table lamp, the bottom of the shade should be close to your eye level. This stops the bare bulb shining into your eyes. Bedside lamps and lamps next to sofas usually look best when the whole lamp is between 60 and 80 cm tall.
Quick Size Guide
| Lamp base height | Suggested shade diameter | Suggested shade height |
|---|---|---|
| 20 to 30 cm | 20 to 25 cm | 15 to 20 cm |
| 30 to 40 cm | 25 to 35 cm | 20 to 25 cm |
| 40 to 50 cm | 35 to 40 cm | 25 to 30 cm |
| 50 to 60 cm | 40 to 45 cm | 30 to 35 cm |
| Floor lamp | 40 to 50 cm | 30 to 40 cm |
These are starting points rather than strict rules. A slim, tall base can take a narrower shade, while a round, chunky base usually needs a wider one.
Sizing Floor Lamp Shades
Floor lamps are taller and stand on their own, so they need bigger shades, usually 40 to 50 cm across. Make sure the shade is high enough that you do not see the bulb when you are sitting down, and wide enough to look in proportion with your sofa or armchair.
Sizing Ceiling Shades and Pendants
For a ceiling light shade, a popular rule is to add the length and width of the room in feet, and use that number as the shade’s diameter in inches. For example, a room that is 12 feet by 14 feet adds up to 26, so a shade about 26 inches (around 65 cm) across would suit it. In rooms with low ceilings, keep at least 2.1 metres of clearance below the shade so people do not bump into it.
Choosing the Right Shape
- Drum shades: straight sides, a modern look and an even spread of light. They suit most bases.
- Empire shades: narrower at the top and wider at the bottom, a classic choice that directs more light downwards.
- Coolie shades: a wide, cone shape that throws light down, ideal for reading.
- Square or rectangular shades: suit square bases and angular furniture.
A useful tip is to match the shape of the shade to the shape of the base: round with round, square with square.
Lampshade Fittings Explained
Most shades sold in the UK use a duplex fitting, which lets the same shade sit on a table lamp or hang from a ceiling pendant by flipping the fitting ring. Other fittings include harp fittings, where the shade sits on a frame with a finial, and clip-on fittings that attach to the bulb. Check the fitting before you buy, and use a reducer ring if the hole is too large for your lamp.
Safety Tips
- Never use a bulb with a higher wattage than the lamp or shade allows.
- Choose LED bulbs, which produce much less heat than old incandescent bulbs.
- Leave space between the bulb and the fabric of the shade.
- Keep fabric shades away from curtains and other materials that could catch fire.
Common Lampshade Mistakes to Avoid
- Choosing a shade that is too small, which makes the lamp look top-heavy.
- Buying a shade that shows the bulb or fitting from the side.
- Ignoring the fitting type and finding the shade does not fit.
- Using a dark, thick shade where you need bright light for reading.
Frequently Asked Questions
How do I know what size lampshade I need?
Measure the width and height of your lamp base. Choose a shade about twice as wide as the base and about two-thirds of its height.
Should a lampshade be wider than the base?
Yes. The shade should be wider than the widest part of the base, ideally by at least 2.5 cm on each side.
What is a duplex lampshade fitting?
A duplex fitting is a reversible ring that lets one lampshade fit either a table or floor lamp or a ceiling pendant.
How high should a lampshade be on a table lamp?
When you are seated beside the lamp, the bottom of the shade should be close to your eye level so you do not see the bare bulb.
Can a lampshade be too big?
Yes. A shade that is much more than twice as wide as the base, or that hides most of the base, can look out of proportion and may make the lamp unstable.
Final Thoughts
Choosing the right lampshade size is easy once you know the basic rules: about twice as wide as the base, about two-thirds of its height, and low enough to hide the bulb. Match the shape and fitting to your lamp, use cool-running LED bulbs, and your lamp will look balanced and give the right kind of light. For more lighting ideas, read our guides on how to light a room without ceiling lights and choosing a plug-in wall lamp, or browse all our home and decor guides.
