Christmas Light Sizes & Styles
Find the Right Christmas Light
for Your Display
Christmas light bulbs are typically identified by a combination of a letter and a number (such as M5, C6, C7, C9, or G12).
The letter indicates the bulb's shape.
The number refers to the bulb's size:
For cone-shaped bulbs, the number represents the diameter in eighths of an inch.
For globe-shaped bulbs, the number represents the diameter in millimeters (mm).
Cone-Shaped Bulbs
These classic holiday bulbs are among the most popular choices for both indoor and outdoor decorating.
C6 Bulbs
Diameter: 6/8" (0.75")
Often called "strawberry bulbs," C6 lights provide a charming, delicate glow and are ideal for:
- Indoor Christmas trees
- Wreaths and garlands
- Small outdoor accents
- Window displays
C7 Bulbs
Diameter: 7/8"
Base: E12 (Candelabra)
A step up in size and brightness from C6 bulbs, C7 lights are commonly used for:
- Indoor Christmas trees
- Doorways and windows
- Roofline accents
- Decorative trim lighting
C9 Bulbs
Diameter: 9/8" (1.125")
The traditional choice for large outdoor displays, C9 bulbs are larger, brighter, and highly visible. Best for:
- Rooflines
- Walkways
- Outdoor trees
- Commercial displays
- Large focal points
Globe-Shaped Bulbs
Round globe bulbs create a softer, decorative lighting effect and are popular for patios, outdoor entertaining spaces, and modern holiday displays.
G12 Bulbs
Diameter: 12 mm
A small, round bulb that provides subtle illumination.
Ideal for:
- Patio accents
- Outdoor shrubs
- Modern holiday displays
- Soft decorative lighting
G30 Bulbs
Diameter: 30 mm
Slightly larger than a ping-pong ball, G30 bulbs are commonly used in:
- Patio string lights
- Pergolas
- Decorative outdoor seating areas
G40 & G50 Bulbs
Diameter: 40–50 mm
These larger globe bulbs approach the size of a tennis ball and create a bold decorative effect.
Common applications:
- Indoor decorative lighting
- Outdoor patios
- Bistro-style lighting
- Entertainment spaces
Mini String Lights
Mini lights are inspired by traditional incandescent mini bulbs but are available in modern LED versions as well.
Diameter: Approximately ¼"
Best used for:
- Wrapping trees
- Porch railings
- Indoor decorating
- Garland and wreath lighting
Their compact size allows for dense coverage and a clean, elegant appearance.
Patio & Specialty Lighting
The bulb base determines which socket the bulb fits.
E26 Patio Bulbs
These bulbs use a standard household socket and are commonly found in:
- Patio string lights
- Porch lighting
- Outdoor entertainment areas
- Decorative café-style installations
Icicle Lights
Icicle lights feature vertical drops that create the appearance of hanging icicles.
Typical drop lengths include:
- 9"
- 12"
- 15"
These lengths are often repeated in a pattern to create visual depth and a realistic icicle effect along:
- Roof eaves
- Gutters
- Fences
- Porch overhang
Quick Size Comparison
Mini lights are inspired by traditional incandescent mini bulbs but are available in modern LED versions as well.
Understanding Light Bases
The bulb base determines which socket the bulb fits.