C7 vs C9 side by side
The C is for the candle or cone shape, and the number is the diameter in eighths of an inch: a C7 is 7/8 inch across and a C9 is 9/8, or 1⅛.
| C7 | C9 | |
|---|---|---|
| Diameter | ⅞ in. | About 1⅛ in. (Wintergreen lists 1.18 in.) |
| Length | About 1½ in. | About 2¼ in. |
| Base | E12 candelabra, 12 mm | E17 intermediate, 17 mm |
| Incandescent watts | 5 or 7 W | 7 or 10 W |
| LED watts (Wintergreen OptiCore) | 0.8 W, 22 lumens | 0.8 W, 25.5 lumens |
| Stringer spacing | 6 or 12 in. | 6, 12 or 18 in. |
| Most common spacing | 12 in. | 12 in. on rooflines |
| Where it's used | Porches, walkways, outdoor trees and bushes, mantels, indoor trees | Rooflines, fences and posts, pillars, large outdoor trees, commercial displays |
Which goes where on a house
Rooflines and gables: C9. 1000Bulbs calls C9s the usual bulb for lining roofs because they can be seen from a distance. That's how a roofline is seen: the whole outline, from the sidewalk or across the street.
Porches, railings, walkways and shrubs: C7. These are seen from a few feet away, where the smaller bulb fits the scale. 1000Bulbs lists C7s for porches, walkways, bushes and trees.
Both on one house. You can mix them: C9s on the roofline, C7s on the porch rail or a front shrub. Just buy bulbs to match each stringer, since the bases differ.
Spacing: how far apart the bulbs go
At Christmas Lights, Etc, C9 stringers come with sockets 6, 12 or 18 inches apart, and the store calls 12 inches the most common choice for C9 rooflines; 6 inches gives a dense line for trees and close-up displays. Its C7 stringers come in 6 and 12 inches, with 12 the usual residential choice.
Spacing sets the bulb count. On a 150-foot roofline, 12-inch spacing is 150 bulbs, 15-inch is 120 and 6-inch is 300. Our sister brand’s permanent C9 packages, C9 Classic and C9 Track, use 15-inch spacing.
At the free measure we show you exactly where the lights will go on your house before you decide.
Faceted or smooth, LED or incandescent
LED C9 lenses come two ways. Wintergreen's faceted lens has a diamond-cut pattern that throws a halo of light; its smooth, opaque lens gives the traditional look of classic Christmas bulbs. The bulbs in our seasonal service are faceted.
LED or incandescent matters more to your power bill than C7 or C9. An incandescent C9 draws 7 to 10 watts; Wintergreen's LED C9 draws 0.8. Our guide to LED vs incandescent Christmas lights works out what a whole roofline costs to run on Clark Public Utilities and PGE.
Colors
C7s and C9s both come in a wide range of colors, in LED and incandescent. The colors we stock for seasonal installs: warm white, pure white, red, green, blue, multicolor, red and white, red and green. See how each color looks on a house before you pick.
A seasonal quote for your roofline
Our 2026 first-installation rate is $6.50–$14 per foot, depending on when you pay the 50% deposit. Installation, takedown and storage are included. Reinstallation of our stored lights is $4.50 per foot.
We supply and own the seasonal lights. Choose your roofline and color scheme, then request a free on-site measure. Your written quote confirms the actual footage, scope, tax and installation date. Paying the 50% deposit locks the rate, even when the installation falls in a later price window.
We guarantee a fix within 48 hours for our lights during the season, weather permitting. January takedown is planned for January 2–15 on the date agreed in the quote. We test, label and store the lights until next season. Extra services and customer-supplied lights need separate confirmation.
Sources & further reading
Research originally checked September 26, 2026. Product figures and utility examples are dated research, not a quote for your installation. Follow current product labels and check the original source for updates.
- 1000Bulbs: C7 vs. C9 Christmas lights
- Wintergreen Lighting: C7 warm white OptiCore LED bulbs
- Wintergreen Lighting: C9 warm white OptiCore LED bulbs, faceted
- Wintergreen Lighting: C7 clear transparent incandescent bulbs, 5 and 7 watt
- Wintergreen Lighting: C9 clear transparent incandescent bulbs, 7 and 10 watt
- Christmas Lights, Etc: C7 light strings and spools, spacing guide
- Christmas Lights, Etc: C9 light strings and spools, spacing guide
- Wintergreen Lighting: C9 opaque (smooth) warm white OptiCore LED bulbs