Types of Christmas Lights: The Complete Guide to Every Bulb Shape and Style
Types of Christmas Lights: The Complete Guide to Every Bulb Shape and Style
Every Christmas Light Bulb Type, Explained
C7, C9, 5mm, M5, G12, G50 — the letter-number soup of Christmas light bulbs confuses even experienced decorators. Each designation refers to a specific bulb shape and size, and each has a purpose. Pick the right type for the right application and your display looks intentional. Pick wrong and something feels off, even if you can't pinpoint why.
Here's every major Christmas light bulb type, what it looks like, where it works best, and what to consider before you buy.
C7 and C9 Bulbs: The Classic Roofline Lights
C7 bulbs are the smaller of the two classic "strawberry" shapes — about 2 inches tall with a candelabra (E12) base. They produce a focused, jewel-like glow that works well on smaller homes, window frames, and fence lines. The scale is intimate — festive without dominating.
C9 bulbs are the big ones. About 3 inches tall with an intermediate (E17) base, these are the quintessential roofline bulb. They're visible from a distance, throw substantial light, and create that bold, retro look that defines American Christmas decorating. If you picture a perfectly decorated home from the street, you're picturing C9s on the roofline.
LED vs. incandescent: Modern LED C7 and C9 bulbs use faceted or smooth plastic lenses over an LED chip. They run cool, draw minimal power, and are available in a wide range of colors. Incandescent C7s and C9s have that warm, glowing filament look — but they run hot, draw more power, and burn out faster. For roofline use, LED is the practical choice.
Retrofit vs. stringer sets: C7 and C9 systems typically use separate stringers (the wire with sockets) and bulbs (which screw in individually). This is actually an advantage — you can replace individual bulbs, change colors year to year, or mix colors within a single stringer. Stringer sets come in various socket spacings, with 12-inch and 15-inch being most common for rooflines.
5mm Wide Angle LED: The Workhorse Mini Light
The 5mm wide angle LED is the modern successor to the traditional mini light. The "wide angle" refers to a conical lens shape that distributes light in a broad, even pattern — unlike older mini LEDs that threw a narrow beam straight out from the bulb tip.
These are the most versatile Christmas lights in existence. They work on trees, bushes, wreaths, garlands, window frames, railings, fences — anywhere you need dense, even coverage. They're lightweight enough not to weigh down branches, cool enough to touch immediately after turning off, and efficient enough to connect dozens of strings end to end.
Available in virtually every color and color combination imaginable — including The Christmas Light Emporium's exclusive ColorSplash palettes — 5mm LEDs are the default choice for most residential and commercial decorators.
M5 Mini Lights
M5 bulbs are small, rounded, berry-shaped LEDs — think of them as a rounder, softer alternative to the conical 5mm. The light output is similar, but the shape creates a slightly different aesthetic. M5s look like tiny glowing berries, which gives them a more organic, natural appearance on trees and wreaths.
They're less common than 5mm wide angle bulbs but have a dedicated following among decorators who prefer their softer visual profile. If you're wrapping a tree and want something that feels less "techy" than the sharp conical 5mm, M5s are worth considering.
G12 Raspberry Lights
G12 bulbs are small globe-shaped LEDs — about the size of a raspberry. They produce a round, faceted glow that's distinct from both the conical 5mm and the smooth M5. The globe shape scatters light in all directions, creating a sparkly, jewel-like effect.
G12s are popular for tree wrapping and garlands where you want a bit more visual weight than a standard mini light without stepping up to the scale of a C7. They're also a favorite for commercial displays — the faceted globe catches light beautifully and reads well from a distance.
G25, G40, and G50 Globe Lights
Globe lights are the round, ball-shaped bulbs you see on patios, event spaces, and upscale outdoor dining areas. The number indicates approximate diameter in millimeters:
- G25 (1 inch): Small globe, intimate scale. Works on smaller patios and indoor installations.
- G40 (1.5 inches): The most popular patio globe size. Visible without being overwhelming.
- G50 (2 inches): Large, dramatic globes. Best for commercial spaces, large patios, and event venues where scale matters.
Globe lights aren't typically used for traditional Christmas roofline or bush wrapping — they're more of a permanent outdoor lighting or event solution. But many homeowners integrate them into year-round patio setups and switch color temperatures seasonally.
Icicle Lights
Icicle lights aren't a different bulb type — they're a different string configuration. The main wire runs horizontally (along a roofline or gutter), and shorter vertical "drops" hang down at regular intervals, creating an icicle effect. Drop lengths typically vary between 12 and 24 inches to mimic the randomness of real icicles.
Cool white and blue icicle lights create the most realistic frozen-water effect. Warm white reads more as a decorative accent. Multicolor icicle lights exist but tend to undermine the "icicle" illusion — if you want color on your eaves, C9 stringers usually deliver a cleaner look.
Net Lights
Net lights are pre-configured grids of mini LEDs designed to drape over bushes, hedges, and shrubs. Instead of individually wrapping each plant — which can take hours — you lay a net light over the bush, anchor the corners, and you're done in minutes.
The grid spacing is typically 6 to 12 inches between bulbs, which provides even coverage without gaps. They're available in warm white, cool white, multicolor, and various single colors. For homeowners with a row of boxwoods or foundation plantings, net lights are a massive time-saver.
Rope Lights
Rope lights encase small LED bulbs inside a flexible, clear or colored PVC tube. The result is a continuous line of light that can follow curves, outline architectural features, or line pathways. They're waterproof by design and incredibly durable.
Rope lights work best for outlining — tracing a window frame, lining a walkway, or defining a geometric shape. They don't produce the individual-point sparkle of traditional string lights, so they're best used as accent elements alongside other light types rather than as a primary display light.
Frequently Asked Questions
What's the difference between C7 and C9 Christmas lights?
C7 bulbs are about 2 inches tall with a candelabra base, while C9 bulbs are about 3 inches tall with a larger intermediate base. C9s are the standard roofline bulb — bold and visible from the street. C7s work better on smaller homes, fences, and window frames where a subtler scale fits.
What type of Christmas lights are best for wrapping trees?
5mm wide angle LED mini lights are the standard choice for tree wrapping. They're lightweight, produce even illumination in all directions, run cool against bark and foliage, and are available in enough string lengths to handle trees of any size. M5 and G12 bulbs are alternatives if you want a different aesthetic.
What are the best Christmas lights for a roofline?
LED C9 bulbs on commercial-grade stringers are the go-to choice for rooflines. They're large enough to be seen from the street, available in a wide range of colors, and the stringer system lets you replace individual bulbs or change colors each season. C7s work for smaller rooflines where C9s would look oversized.
What does "5mm wide angle" mean for LED Christmas lights?
The "5mm" refers to the LED chip size, and "wide angle" describes the conical lens shape that spreads light in a broad 160-degree pattern. This design replaced older LED mini lights that projected a narrow beam straight forward. Wide angle LEDs provide even, all-around illumination similar to traditional incandescent mini lights.
Can I mix different types of Christmas lights in one display?
Yes — and you should. A well-designed display uses different light types for different elements: C9s on the roofline for bold visibility, 5mm mini lights on trees and bushes for dense coverage, net lights on foundation plantings for easy installation, and maybe icicle lights on the eaves. Mixing types adds visual depth and interest.
Are LED Christmas lights better than incandescent?
For most applications, yes. LED Christmas lights use up to 90% less energy, run cool to the touch, and handle far more connections per circuit. Incandescent bulbs still have fans who prefer their warm filament glow, but LED technology has largely closed the color-quality gap — especially in warm white tones.
What's the difference between net lights and mini light strings?
Net lights are pre-configured grids that drape over bushes for quick, even coverage. Mini light strings require you to wrap each plant individually. Net lights save significant installation time on foundation plantings, while mini strings offer more flexibility for custom wrapping patterns on trees and irregular shapes.
Build Your Display by Type
Now that you know what each bulb type does, building a cohesive display gets a lot simpler. Match the light type to the job, stick to a consistent color temperature across types, and don't be afraid to mix — variety in bulb shapes is what gives professional displays their depth.
Start with our LED C9 bulbs and stringers for the roofline. Add 5mm LED mini lights for trees and wrapping. Finish with net lights on foundation plantings for fast, even coverage. And if you want color combinations nobody else on your street has, explore the ColorSplash collection.
