Lampshade diameter size guide showing 20cm, 20cm, 35cm and 40cm drum lampshades for table lamps

This visual guide shows the most common drum lampshade diameters used on table lamps.

Lampshade Measuring Guide

Find the perfect size shade for your lamp.

At the end of the day, there’s no such thing as the “wrong” lampshade—if you love how it looks, that’s what matters most! But if you're looking for some helpful guidelines, we’ve got you covered.

Measuring a lampshade correctly helps ensure your replacement shade fits your lamp base and looks balanced in proportion. This guide explains how to measure lampshade diameter, height, and slant so you can confidently choose the right size for your table lamp or floor lamp.

Getting Started

A new lampshade can completely transform the look and feel of a room. When choosing a size, think about:

The shape of the lampshade
The style and size of the lamp base
The location it will be used (e.g., side table, console, floor lamp, etc.)

Quick Size Guide

Use the diameter of the shade’s bottom ring as your key measurement:

Small lamp bases 10–15 cm width | 20-30 cm diameter shade
Medium lamp bases 15–20 cm width | 30-40cm diameter shade
Large lamp bases 20-25cm width | 40-45 cm or larger shade

Already have a shade you like? Use those measurements as your reference.

If you're unsure which size lampshade is best for your lamp base, feel free to contact us and we’ll be happy to help.

Quick Lampshade Measuring Guide

Measure the diameter across the bottom of the shade.
Measure the height from the bottom ring to the top ring.
Use these measurements when selecting your new lampshade.

Choosing the Right Proportion

As a general guide:

The lampshade diameter should be around twice the width of the lamp base.
The height of the shade should be approximately one third of the lamp base height.
Consider the shape of lampshade, style of lamp base and location of lampsahde

What size lampshade do I need?

There is no single rule but the simplest way to measure the size of lampshade required is keep the lampshade size in proportion to the lamp base.

How to Measure for a Lampshade

1. Diameter

Measure the widest part of the lamp base, then double that number.
Example: A 15 cm wide base = a 30 cm diameter lampshade.

2. Height

Measure from the bottom of the base to just below the bulb holder.
Your shade height should be around 70% of this measurement.

If these measurements do no look correct for your base try the following tips for a great fit:

The +/- 5cm Rule:
Take the total height of the lamp base. Your shade’s diameter should be about ±5 cm of that height.
Example: For a 40 cm base, go for a 35–45 cm wide shade.
Width = Height:
The bottom diameter of your shade can be roughly equal to the lamp base height.
2/3 Rule:
The lampshade height should be about two-thirds of the lamp base height.
Wider than the base:
The lampshade should always be a bit wider than the widest part of the lamp base for visual balance.

Choosing the right lampshade for a floor lamp can be a little tricky due to their tall, slender form. Here are some helpful tips to guide you:

Recommended Sizes:

Small floor lamps: Use a shade with a minimum 30 cm diameter
Standard floor lamps: Opt for a 45 cm diameter or larger for a balanced look

Top Tips

Height ÷ 4: Measure from the floor to just below the bulb holder, then divide that height by four to estimate the ideal shade height.
Pendant Position: If your lamp has an arc-style arm or the fitting is at the top, you’ll need a ceiling pendant-style shade.
Consider the Shape:
- Drum shades offer a bold, spacious look but take up more room
- Oval shades are great for tighter spaces
- Empire shades add vertical height and elegance

Location Matters
Keep the room size in mind—a large shade might feel overwhelming in a small space, while a spacious room can handle a more dramatic design.

Wall lamp in modern loft apartment. Wall sconce on white brick wall. Yellow lights in shad

WALL LIGHTS

For wall fittings, smaller shades work best. Make sure to measure the depth from the wall to the light fitting to ensure the shade doesn’t stick out too far.

Ideal Shapes for Wall Lights:

Candle clip shades
Small drums
Rectangles, ovals, and square shades

Choosing the right shape?

The shape of your lampshade is a matter of personal style, but here are some general tips:

Round lamp bases: Pair well with drum, empire, or conical shades
Straight-edged or angular bases: Look great with square or rectangular shades
Column-style bases: Extremely versatile—suit almost any shade shape

Tip: Keep location in mind—large drum shades take up more space, while oval or rectangular shades can fit neatly against a wall or in narrow spaces.

Need Something Custom?

Berry & Grouse offers a wide variety of standard lampshade sizes and shapes, but if you need something bespoke, we’re happy to help! Click here to explore our range of shapes and sizes or get in touch for custom options.

Because our lampshades are handmade to order, we recommend checking your measurements carefully before placing your order.

Now that you know how to measure your lampshade, explore our collection of handmade lampshades available in a variety of shapes and sizes.

Learn more about different lampshade shapes and fittings in our Lampshade Buyer’s Guide.

FAQ's

How do you measure a lampshade? Measure the bottom diameter of the shade and the height from the bottom ring to the top ring.

Should you measure the top or bottom of a lampshade? The bottom diameter is usually the most important measurement.

What size lampshade do I need? A common guideline is that the shade diameter should be roughly twice the width of the lamp base.

How tall should a lampshade be? The shade height is usually around one third of the lamp base height.

Can I replace my lampshade with the same size? Yes — measuring your existing lampshade is usually the easiest way to select a replacement.