Choosing the correct light bulb shape is just as important as selecting the right brightness, colour temperature or base cap. Different LED bulb shapes are designed for different light fittings, decorative styles and lighting effects. From standard GLS bulbs and Candle lamps to Globe, ST64 Edison, Tubular and Spotlight bulbs, each shape serves a specific purpose. This guide explains the most common light bulb shapes, what they're used for and how to choose the right lamp for your home or commercial lighting project.
Quick Answer: What Is a Light Bulb Glass Shape?
A light bulb glass shape refers to the external design and profile of the bulb.
Common bulb shapes include:
- A60 GLS (Standard Pear Shape)
- C35 Candle
- G45 Golfball
- G95 Globe
- ST64 Vintage Edison
- ST26 Pygmy
- T45 Radio
- T30 Tubular
- GU10 Spotlight
- G9 Capsule
- G4 Capsule
Each shape is designed for specific fittings, lighting effects, and decorative applications.
NB! Before choosing a bulb shape, identify the correct light bulb base cap.
Why Does Bulb Shape Matter?
The shape of a light bulb affects:
- Light distribution
- Decorative appearance
- Compatibility with fittings and shades
- Visibility of the bulb
- Overall room aesthetics
For example, a decorative pendant light often looks best with a vintage filament globe or ST64 bulb, while a table lamp may use a traditional GLS lamp.
What Glass Shapes Does Zico Lighting Offer?
At Zico Lighting, we stock a wide variety of LED lamp shapes to suit virtually every lighting application.
Whether you're looking for classic household lamps, decorative filament bulbs, or specialist lighting products, we have options to match your requirements.
A60 GLS Bulbs (General Lighting Service)
A standard A60 GLS bulb measures 60mm diameter (A60) and is the most common household light bulb.
How to identify a GLS bulb:
- Classic bulb shape
- Rounded top
- Tapered neck
- Usually available with E27 (ES) screw cap or B22 (BC) bayonet cap.
Common uses:
- Ceiling lights
- Table lamps
- Floor lamps
- General household lighting
GLS bulbs remain one of the most popular options for everyday lighting.
Candle Bulbs
Candle bulbs are designed to mimic the appearance of a candle flame. There a 3 shapes available: classic C35 Candle and C35 Flame Tip, both measuring 35mm in diameter, and a smaller C22 French Candle with diameter of 22mm.
How to identify a candle bulb:
- Slim profile
- Pointed tip
- Elegant decorative appearance
- C35 Classic Candle is commonly available with E27 and E14 screw caps, as well as B22 and B15 bayonet caps. C22 and C35 Flame Tip usually come with smaller base caps, such as E14, E10 and B15.
Common uses:
- Chandeliers
- Wall lights
- Decorative fittings
- Hospitality lighting
Candle lamps are particularly popular when the bulb remains visible within the fixture.
G45 Golfball Bulbs
G45 Golfball bulbs are compact spherical lamps, measuring 45mm in diameter and approximately 80mm in height, including the base cap.
How to identify a golf ball bulb:
- Small round shape
- Compact size
- Similar appearance to a golf ball
- G45 can come with more common E27 and B22 base caps, but also with smaller E14 and B15 base caps, making it suitable for a wide range of light fittings.
Common uses:
- Wall lights
- Decorative lamps
- Small fittings
- Bathroom lighting
These lamps are ideal where space is limited.
Globe Bulbs
Globe bulbs provide a striking decorative appearance and are increasingly popular in modern interiors. Globe bulbs come in various sizes, bust more common ones include G80, measuring 80mm in diameter, G95 with diameter of 95mm and a large and striking G125 with diameter of 125mm.
The G95 Globe bulb is one of the most popular decorative lamp shapes available today. Its large spherical design makes it ideal for exposed fittings where the bulb itself forms part of the overall aesthetic.
Notably, G45 Golfball is also a Globe, but due to its popularity, it is often listed as a separate category.
How to identify a globe bulb:
- Large spherical shape
- Available in various diameters
- Often supplied with visible LED filaments
- Due to its large size, the Globe usually comes fitted with E27 (ES) screw cap or a B22 (BC) bayonet cap.
Common uses:
- Pendant lighting
- Feature lighting
- Restaurants
- Hotels
- Retail environments
Large globe lamps create a premium decorative effect while providing excellent illumination.
ST64 Vintage Edison Bulbs (Squirrel Cage)
The ST64 Squirrel Cage is one of the most popular decorative filament lamp styles with elegant shape and a diameter of 64mm at the widest point.
How to identify an ST64 bulb:
- Elongated teardrop shape
- Visible LED filaments
- Vintage-inspired design
- Usually fitted with E27 (ES) screw cap or a B22 (BC) bayonet cap.
Common uses:
- Industrial interiors
- Restaurants
- Bars
- Decorative pendant lighting
ST64 lamps combine classic styling with modern LED efficiency.
Tubular Bulbs
Tubular lamps feature a slim cylindrical design and come in variety of sizes and length.
Common types include:
- T20 Tube, measuring 20mm diameter
- T30 Tube with diameter of 30mm and 2 popular lengths of approximately 185mm or 300mm
- T25, also known as picture light due to the shape perfect to light up artwork, is 25mm diameter
- T45 Radio has a chunkier 45mm diameter and is particularly popular where a traditional bulb appearance is desired while maintaining a compact footprint.
How to identify a tubular bulb:
- Straight-sided profile
- Narrow diameter
- Extended length
- Smaller Tubulars, such as T20 and T25 usually come with E14 (SES) base cap, while the T30 and T45 Tube lamps have E27 (ES) base cap.
Common uses:
- Decorative fixtures
- Wall lights
- Display lighting
- Contemporary fittings
These lamps offer a clean and minimalist appearance.
Spotlight Bulbs
Spotlights are designed to direct light into a focused beam.
Common types include:
- GU10 spotlights are identified by the 2-pin GU10 base cap and come in varying diameters
- Directional LED bulbs
Common uses:
- Kitchens
- Bathrooms
- Retail displays
- Accent lighting
These bulbs are designed for task and feature lighting applications.
Capsule Bulbs
Capsule lamps are compact bulbs used in specialist fittings.
Common types include:
- G9, measuring approximately 64mm in height and 18mm in diameter and fitted with G9 2-prong base cap
- the smaller and more discreet G9 mini, with height of 50mm and diameter at 16mm
- G4 is only 10mm in diameter and 35mm in height including connectors. Most G4 Capsules are low voltage, meaning they should not be plugged in directly into mains electricity, but require a transformer.
Common uses:
- Decorative lighting
- Cabinet lighting
- Display units
- Feature fittings
Their small size makes them ideal for discreet lighting solutions.
ST26 Pygmy Lamps
ST26 Pygmy lamps are compact, narrow bulbs commonly used in specialist and decorative applications where space is limited.
How to identify an ST26 Pygmy lamp:
- Slim tubular profile
- Small diameter (approximately 26mm)
- Compact overall size
- Often available with clear or frosted finishes
- Come fitted with E14 (SES) screw cap or B15 (SBC) bayonet cap.
Common uses:
- Picture lights
- Display cabinets
- Signage
- Decorative fixtures
- Appliance lighting
- Accent lighting
Due to their compact design, ST26 Pygmy lamps are ideal where a standard-sized bulb would be too large for the fitting.
Which Bulb Shape Should I Choose?
The best bulb shape depends on the fixture and the desired appearance.
Choose a GLS bulb if:
- You need general-purpose household lighting.
- The bulb is hidden by a shade or fitting.
Choose a Candle bulb if:
- The bulb is visible.
- You want a traditional decorative appearance.
Choose a Globe bulb if:
- You want a modern statement feature.
- The fitting showcases the bulb.
Choose an ST64 bulb if:
- You prefer vintage or industrial styling.
- Decorative aesthetics are important.
Choose a spotlight if:
- You need directional lighting.
- The space requires task illumination.
Frequently Asked Questions About Light Bulb Shapes
What is the most common light bulb shape?
The GLS (General Lighting Service) bulb is the most common household light bulb shape in the UK.
What is an ST64 bulb?
An ST64 bulb is a decorative vintage-style lamp with an elongated teardrop shape and visible filament design.
Are globe bulbs brighter than standard bulbs?
Not necessarily. Brightness is measured in lumens, not shape. Globe bulbs can be supplied in various lumen outputs. Understand lumens vs watts.
Can I use any bulb shape with my fitting?
Only if the bulb physically fits within the fixture and uses the correct base cap. Always check dimensions before purchasing. Learn more about base caps.
Does bulb shape affect light output?
The shape itself doesn't determine brightness, but it can influence how light is distributed throughout a room.
Expert Advice from Zico Lighting
Choosing the right bulb shape can completely transform the look and feel of a lighting installation.
In addition to the extensive range of LED lamp shapes, all Zico Lighting decorative LED lamps combine premium aesthetics with professional lighting performance, including CRI 95+ colour accuracy, R9 >90, flicker-free operation, smooth dimming, and excellent SDCM colour consistency for reliable, natural-looking illumination.
Whether you're updating your home, fitting out a restaurant, or specifying commercial lighting, our team can help you find the perfect lamp shape for your project.
Final Thoughts
Whether you're replacing a household bulb, choosing decorative lighting for your home, or specifying premium LED lamps for hospitality and commercial projects, selecting the correct bulb shape ensures the best fit, appearance and lighting performance. From classic GLS bulbs and elegant Candle lamps to statement Globe bulbs, vintage ST64 Edison lamps and specialist Capsule fittings, Zico Lighting offers high-quality LED lighting solutions designed to combine exceptional aesthetics with professional-grade performance.
Related Guides
How to identify a light bulb base cap
Understanding Colour Temperature (CCT) and why it matters
How to choose a dimmable LED bulb