Why you should trust us

It wasn’t easy to pick out these specific models from the seemingly infinite selection of Christmas lights in the world. But we reached our conclusions with the input of several people who live and breathe lights: Ben Orr, owner of Northern Seasonal Services, who has been professionally installing holiday lighting in the Chicago area since 2005; Jason Woodward, the director of ecommerce at Christmas Designers, a retailer specializing in holiday lighting; John Strainic, GE‘s general manager of North America consumer lighting; and Anthony Krize, vice president of Nicolas Holiday, the brand-management company for GE’s Christmas lights.

We also enlisted the aid of professionals in our testing process to help us assess the color quality of each string light set. In previous years, we consulted Susan Moriarty, executive creative director and founder of the Boston-based creative agency The Soapbox Studio, who has 20 years of experience as an art director, designer, and photographer. For our 2019 testing, we relied on the eyes of Bridget Collins, the interim lighting and projections supervisor at the Tony Award–recognized Huntington Theatre Company, a Boston theater where guide co-author Thom Dunn was a writing fellow from 2015 to 2017.

How we picked

Many different kinds of Christmas string light bulbs are available, and many people already know what they like—even if they don’t necessarily know that a type of light is called a C9 or an M5 or anything else. For this guide, however, we focused on the standard nonblinking miniature (or T5) lights. These are the small, traditional, candle-shaped Christmas lights that most people are used to. As this DIY Network article says, even though larger bulbs are growing in popularity, “mini lights have been by far the most popular during the past decade,” and we confirmed this in our conversations with Jason Woodward of Christmas Designers and Anthony Krize of Nicolas Holiday/GE Brands. During our research, we also found that blinking lights represent a very small minority of the available lights, so we stayed with the type that remains lit at all times.

The earliest Christmas lights were incandescent—that is, they got their glow from a heated filament inside the glass bulb, like any other commercial light bulb. This component creates a nice, warm radiance in the room that many people associate with the holiday season. Since the early 2000s, however, LED Christmas lights have become increasingly popular, and they’re often easier to find now than the traditional incandescent ones. LEDs tend to cost more than their incandescent counterparts, but they also last longer, use a lot less electricity, and thus produce less heat, which makes them safer overall. As Jason Woodward from Christmas Designers told us, “the benefits offered by LEDs are almost as significant as the benefits that incandescents provided over candles.” Some people are understandably hesitant to use LEDs—older or poorly made LEDs can sometimes be too bright or cause a kind of nauseating strobe effect. But the technology has advanced enough in recent years that we feel confident recommending them. However, we still sought out some incandescent options for people who prefer that traditional warmth.

Many LED Christmas lights can work well indoors or outdoors. For outdoor lights, our experts directed us toward a specific style of LED: 5-millimeter wide-angle conicals. The bulbs on these lights are stubby and don’t have the homespun look of the small glass candle found on other mini lights. They are much brighter than regular mini lights (both LED and incandescent), and the unique shape of the bulb adds depth and complexity to the lights’ appearance. As lighting installer Ben Orr of Northern Seasonal Services told us, this shape allows the strand to “refract the light and create a cool look depending on the angle of view.” Orr continued, “It appears that some are brighter than others and it adds contrast.” He added that 5 mm wide-angle lights are generally his favorite light. And Christmas Designers, in a video dedicated to the bulbs, says these lights are “by far the most popular set we sell.”

But as with regular LED bulbs, the color of the light is a concern. We figure that if you’re reading this guide, you’re probably interested in replacing an old set of incandescent lights—but even if you want something more efficient and durable, you probably don’t want to give up the traditional lights’ familiar warm glow. Unfortunately, that is an issue with LEDs.

Both Orr and Woodward warned us that LEDs simply do not look like incandescents. Due to improvements in technology, many companies manufacture a “warm white” color that, depending on the quality of the LED, can closely mimic but not fully achieve the pinpoint sparkle of an incandescent. Orr stressed that “LED technology varies throughout the industry, and a warm white from one supplier can vary in hues and color drastically from another.” He even suggested buying strands from a few different manufacturers to compare them and see which hue you like best before making a large purchase—once you find something you like, he said, buy from only that manufacturer. Our testing confirmed that there is a tremendous variety in LED color hues, from the fantastic to the terrible.

In selecting the strands we wanted to test, we searched all of the larger online retailers (Amazon, Home Depot, Lowe’s, Target, Walmart). Orr told us that he purchases his lights from a specialty retailer, so we also looked at lights from Christmas Designers, Christmas Lights Etc, and Christmas Light Source. These specialty retailers deal only in Christmas lights and focus on the needs of the professional, though they certainly have no problems with a regular shopper purchasing from them. Each store seems to have its own in-house brand of lights, so you won’t see them selling Martha Stewart or GE lights. We’ve found that these companies are extremely knowledgeable about lighting, and in general their items are very nice.

We dismissed companies that had overall poor reviews (Holiday Time), strange or incomplete bulb selections (EcoSmart), or suspiciously low pricing (Home Accents Holiday). Other companies, such as Hometown Evolution, AGPtek, and Deneve, fall more into the general exterior-decor category and don’t have a wide selection of Christmas lights. AGPtek, in particular, deals only in solar-powered or battery lights, which are more of a specialty item, and we wanted to concentrate on general tree and exterior lighting.

How we tested

Ready to begin testing. Photo: Doug Mahoney

Since 2014, we’ve tested dozens of string light sets in both white and multicolor, including standard T5 LEDs, incandescents, and 5 mm wide-angle conical LEDs. For our most recent tests in 2019, we looked at 11 sets of white lights, eight sets of multicolor lights, and one set of color-changing lights. To evaluate all of the sets, we wound and unwound them and arranged them around a home, including wrapping them around poles and draping them over railings—basically, we tried to use the lights how they’re intended to be used.

We then took them to a dedicated black-box theater space at the Huntington Theatre Company in Boston, which has transferred numerous plays to Broadway and London’s West End. We set up all the light sets in a pure black space and evaluated them for color temperature and accuracy with the help of the company’s theatrical lighting supervisor, Bridget Collins. (In previous years we’ve relied on similar outside expertise from Susan Moriarty, executive creative director and founder of The Soapbox Studio, also in Boston.) Afterward, we tested the weather impermeability of each set by sinking the lights into a 5-gallon bucket of water and leaving it outside in the cold rain overnight (the temperature didn’t drop below freezing). Although this test is a bit extreme, it’s certainly possible that any set of exterior lights will end up in a puddle or draped in a gutter.

Overall, we found that the wire quality has a lot to do with the success of a strand of lights. Some of the tested lights had tidy, close-knit strands of wire, while others were loose and messy. Some wires needed untwisting before use, like an old phone cord, and still others continued to accordion back on themselves no matter how we tried to stretch them out and lay them flat.

Our pick: GE Energy Smart Colorite LED Miniature Lights

GE was the first company in America to sell Christmas string lights, and we think it still makes the best ones overall. GE’s Energy Smart Colorite LED Miniature Lights are available in multicolor and warm white, and they offer all the benefits of LED lights, including high durability, zero heat output, and a long life expectancy. They also produce a warm radiance that closely resembles the classic glow of incandescent bulbs. There’s no noticeable flicker as on some other LED lights we tested, which were either too dull or glaringly bright and gave us a headache when they moved. The GE Colorites are also well made and durable, with a tightly wound wire that maintains its memory while still being easy to drape on trees or railings (plus, it’s harder to tangle). GE has relied on the same Christmas lights manufacturer for more than 40 years, and that pedigree—and quality—shows. It doesn’t hurt that the lights are widely available online and in stores, too.

GE’s incandescent (top) and LED (bottom) strands. Photo: Doug Mahoney

When it came to color temperature, the Colorites were the clear winner in our tests. The warm white and multicolor strands both gave off a warm tone that was closer to the overall look of an incandescent strand than what we saw from any of the other LEDs we considered. It’s not a 100 percent perfect match from up close, of course—the diode illuminates the entire colored bulb from certain angles, unlike in incandescents, which have a pinpoint filament that creates a twinkly, sparkly look. Note, however, that we made this distinction while specifically looking for differences between the bulbs: Once we were about 5 feet away, it became extremely difficult to tell these LEDs apart from the strand of incandescents, and we would be happy to light up our home with them.

From left: the Christmas Designers warm white incandescents, the GE Colorite warm white LEDs, and the Christmas Designers warm white T5 Smooth LEDs. Notice how the GE LEDs match the color of the incandescents but not their distinctive and even sparkle. The Christmas Designers LEDs have a cooler color and shine a little brighter. Photo: Doug Mahoney

We also liked that the GE Colorite wire strands were easy to manage. In our tests, they were tidy and had a nice flex. Out of the box, the lights unraveled nicely. And unlike other brands we tried, they needed no twisting on our part to stretch and flatten them out. They’re durable enough overall that they should be able to withstand the annual boxing and unboxing process without a hitch.

Instead of having a detachable bulb and a separate socket as an incandescent does, these bulbs encase a light-emitting diode in a block of molded plastic. The result still looks like a traditional Christmas light, but it’s harder to knock a bulb out of commission. Although we don’t suggest that you jump rope with your strands of LED lights, we do believe that they will be able to handle a drop.

From left: the Christmas Designers incandescents, the GE Colorite LEDs, and the Christmas Designers T5 Smooth LEDs. Again, the incandescents have the most consistent sparkle. The GE LEDs match the color (other than the purple), and the Christmas Designers LEDs shine brighter than the others. Photo: Doug Mahoney

We recommend the GE Colorites for indoor use, but they survived our outdoor durability tests, too. If you do end up breaking a bulb, the Colorites’ Constant On feature means the other ones will stay lit until you replace it, which is also possible. When we asked Jason Woodward of Christmas Designers about the lifespan of indoor LEDs, he told us, “High-grade LEDs haven’t been around long enough to really know how long they will last on an indoor application, but it should be at least 10 years.” That longevity should be good news for anyone who has ever pulled out their incandescent lights from the previous year, found a bunch of them mysteriously half-working or suffering from too many blown bulbs, and ended up throwing several away.

Like other LEDs, the GE Colorites emit zero heat when lit, so you can sleep easy while they’re lighting up your desiccated tree on New Year’s Eve. Incandescents, on the other hand, produce heat and can get quite hot—although newer incandescents are highly unlikely to ever start a tree fire, they could give an unsuspecting toddler quite a jolt. The Colorites have such low energy use that you can string together up to 25 sets without a problem (and even that’s pretty ambitious for most homes). The GE Colorite LEDs are also rectified (sometimes called “full wave”), which means they blink fast enough that they shouldn’t have any of those nausea-inducing flicker problems that some other LEDs have. This means you can use them with a dimmer or a lighting controller, too.

The GE Colorites generally cost around 20¢ per light, which is right where most good-quality LEDs land. They’re sometimes sold online under the name Nicolas Holiday, but don’t worry, they’re still the same lights. Either way, they’re a great value for their durability and longevity; there are sets that we bought in 2014 that are still going strong, although the wire strands have loosened a bit.

Flaws but not dealbreakers

Although the GE Energy Smart Colorite LED Miniature Lights impressed us more than the others in both quality and overall color, we did discover a few drawbacks to these lights.

First, they don’t have stackable plugs, the kind of design where the male plug has a female outlet on the back side of it. With stackable plugs, you can piggyback multiple strands directly on the same outlet—a useful feature for outdoor displays where you might be lighting, for example, bushes in opposite directions on either side of a single outlet, but less of a necessity indoors. The lack of such a plug design on the Colorites could make for a crowded wall outlet, but a small power strip will solve the problem. You can still attach the Colorites end to end, just as you would any other set of Christmas lights.

The GE Colorites have a regular plug (left), whereas many competitors, including our runner-up pick, the Christmas Designers T5 Smooth LED Christmas Lights (right), have a stackable plug. The stackable design allows you to have multiple strands on a single outlet. Photo: Doug Mahoney

Christmas-light purists may be dismayed at the look of the purple GE Colorite bulb. In our tests, on the incandescent strands the purple bulb was a deep reddish-pink color, but on the Colorite strand it was a bright, vivid purple that was slightly lavender and almost a little “cartoony.” Once the strands are wound around a tree, we don’t think most people will pick up on this difference, but if you’re color sensitive, it’s something to be aware of. Our runner-up lights don’t have a purple bulb, so they don’t have the same issue.

Finally, we’ve discovered that Christmas lights are manufactured on a seasonal basis, so when they’re gone, they’re gone. For the past few years, these GE lights have sold out in early December and remained unavailable for the rest of the season.

Runner-up: Christmas Designers T5 Smooth LED Christmas Lights

If the GE Colorites are unavailable, we also like the Christmas Designers T5 Smooth LED Christmas Lights, which are available in warm white, multicolor, and solid color. In our tests, the Christmas Designers lights were very similar to the GE Colorites but slightly less bright and less warm.This was true for the white lights as well as the multicolor lights, particularly the yellow and orange (the Christmas Designers lights don’t have a purple bulb). The wires that connect these lights are also tightly wound, which makes them just as easy to wrap up as they are to unravel and maneuver around a tree. On average, the Christmas Designers lights are more expensive than the GE ones, but they’re well made and durable, and the company offers bulk discounts, which can start to even things up depending on the size of your order.

The most obvious way that the Christmas Designers lights stand out from GE’s Colorites is that they have a stackable plug with both an input and output, which allows you to start multiple strands of lights from the same outlet. Unlike the GE Colorites, the Christmas Designers bulbs are made of a single piece of molded plastic. The upside is that this design makes it even harder for dirt and water to infiltrate the bulb and damage the circuitry; these bulbs are likely to be even more resilient outside than the GE bulbs. The downside is that, if a bulb does break, you won’t be able to replace it (but the rest of the string will still work). Otherwise, the LEDs contained within that plastic bulb offer all the same benefits as the LEDs from GE—low energy use, no heat output, and a longer life overall.

Christmas Designers lights are also uniquely available in solid-color strands in addition to the standard warm white and multicolor. They may be a better option if you’re looking to customize a display with green, red, blue, or pure white lights. This is because the company mainly sells to professional installers, although regular-shopper sales have increased significantly in recent years. As Jason Woodward, the company’s director of sales and marketing, told us, “The quickest growing part of our business are the residential, what I call our ‘Christmas enthusiasts’—people who are tired of the Big Box retail junk and are looking for a step up, something that will last longer and look good.” If you’re looking for that kind of sturdy construction—or if the GE Colorites are sold out, which tends to happen closer to the holidays—the Christmas Designers T5 lights are a great alternative.

Also great: Christmas Lights Etc Kringle Traditions Wide-Angle 5mm Outdoor LED Christmas Tree Lights

The Christmas Lights Etc Kringle Traditions Wide-Angle 5mm Outdoor LED Christmas Tree Lights give off a bright, warm color that is particularly perfect for the outdoors, whether you’re decorating a window box, a tree, a wreath, a railing, or a roofline. Christmas Lights Etc—not to be confused with Christmas Designers—also focuses largely on pro installations and thus offers a wide variety of lighting options including white, multicolor, and solid single colors, with different bulb quantities and spacings. Like other LEDs, these lights cost more than incandescents, but since they’re specifically designed to withstand long-term exposure to moisture, your investment will be protected if they end up dropping into a puddle or a wet gutter while braving the elements in a cold, wet December. They also have a clean and tight wire, which in our tests made handling, hanging, and storing them easy. And because their electrical requirements are so low, you can connect a whopping 43 strands and run them on a single outlet before worrying about tripping a breaker; this design reduces the need for extension cords, which can be a big hidden cost with larger exterior displays. These Christmas Lights Etc outdoor lights are slightly brighter than our previous pick from Christmas Designers, but the two are otherwise similar—if you find the Christmas Designers version available in a color you prefer or at a better price, go for it.

The odd, stubby shape of the 5 mm “wide-angle” bulbs gives these lights a distinctive appearance. In addition to the fact that they’re already brighter than many regular LED mini lights, these wide-angle bulbs also emit a different level of brightness depending on the angle from which you view them. In the right situation, this design can almost replicate the “twinkly” look of incandescent lights that many people enjoy.

The Christmas Designers 5mm Wide Angle Conical LED (a former pick, top) and the GE Colorite LED (bottom). Notice the unusual shape of the wide-angle bulb and also how the bulb and socket are molded into a single piece, making such lights ideal for exterior use. Photo: Doug Mahoney

The Christmas Lights Etc wide-angle lights have what are called molded bulbs—that is, each bulb is a completely sealed, one-piece unit. There is no separating the bulb from the wire, and thus no way for moisture or grime to work into the socket, which makes them even better suited for outdoor displays. We tested this design by submerging the lights in a bucket of water outdoors overnight, and at no point did the lights show any ill effects from the test. However, this molded design also means that you can’t replace an individual light if any of them fail (although the rest of the string will keep working). Overall, we think this is a worthwhile trade-off for a bright set of lights that are likely to last even longer than other LED string lights. Just try not to step on the bulbs, and you should be fine.

The Christmas Designers wide-angle multicolored lights, at some point during hour six of being fully submerged in a bucket of water. We put the Christmas Lights Etc lights through the same test in 2019, and they survived just as well. Photo: Doug Mahoney

Like the other lights from pro-installer brands, the Christmas Lights Etc wide-angle LEDs have a great wire. In our tests, they were easy to unravel and didn’t get tangled up like other, lower-quality lights such as the ones from Home Accent Holiday; in fact, the Christmas Lights Etc outdoor lights come in a balled-up clump when they arrive in the package. (We still suggest you wrap them up somewhat carefully when you’re done with them, just to prolong their life.) The neat organization of the wires gave our test strands a high-quality feel, which also gave us confidence that they’d keep running for years regardless of the weather or (most) other abuse they might endure. These lights are also full-wave rectified, so you won’t have any issues with flickering, and you can use them with dimmers if you’d like.

If you have great ambitions for your Christmas display, Christmas Lights Etc also offers a bulk discount for its outdoor lights—the more you buy, the less you pay for each individual set. Although you can use these as indoor lights, we personally found them a bit too bright, and both of the lighting professionals we consulted, in different years, agreed: Susan Moriarty from The Soapbox Studio said, “I don’t want to have to wear sunglasses while I’m looking at my Christmas tree.” If you like your tree to be especially bright, these Christmas Lights Etc lights are a great option, but we recommend that you purchase a single strand first and see for yourself before you take the plunge.

If by some chance the Christmas Lights Etc outdoor lights are unavailable, Christmas Designers sells nearly identical strands of 5 mm wide-angle bulbs in white, multicolor, or solid single colors that are a little dimmer but otherwise just as good.

Also great: Christmas Lights Etc Clear Christmas Tree Mini Lights (incandescent)

LED Christmas lights are better for most people because they’re more efficient and more durable, but if you can’t lose the distinctive and traditional look of incandescents for indoor use, we recommend Christmas Lights Etc’s Clear Christmas Tree Mini Lights. These lights offer a noticeable difference in color quality—they’re not the brightest, but they have a certain warmth and radiance that even the best LEDs struggle to match. It’s the kind of color temperature that immediately sparks memories of cold winter evenings by the fire (or the dive bar). The heated filament inside the bulb gives them that starry sparkle. However, it’s also designed to wear out over time to the point of self-destruction.

In our tests, the wires on the Christmas Lights Etc incandescent lights were tight and organized, and once we stretched them out, they lay flat and straight with no issues. Incandescents will never last as long as LEDs, but the wiring and wrapping on these make them feel sturdy and resilient enough to last for several seasons. They even survived when we submerged them in a water bucket and left it outdoors overnight, although we still don’t think they’re the best choice for outdoor use—it’s too easy for water and dirt to get caught in the sockets. If anything does go wrong and a bulb breaks or dies, incandescent lights are easy and affordable to replace: At this writing, they’re about 10¢ a bulb, which is about half as much as a single LED bulb. Incandescent lights also use more energy, so you can connect only up to five strands of the Christmas Lights Etc incandescents as opposed to 20-plus strands of LED string lights. But if a bulb does go out, the rest of the strand remains lit.

Like most items from Christmas Lights Etc, the incandescent strands are available in a variety of bulb spacings and colors, including multicolor and solid single colors. (We tested only the standard clear white lights.) If they’re unavailable, our previous pick from Christmas Designers is similar and still very good, although that company no longer sells a warm white incandescent option.

Also great: GE Color Choice Multi or Warm White Multi Function LEDs

If you can’t decide between white and multicolor string lights—or if you’re just really into gaudy flashing light patterns—the GE Color Choice Multi or Warm White Multi Function LEDs will give you the best of both worlds. A small control box near the plug end lets you cycle through a variety of lighting options in white and multicolor, from constant-on to a gradual pulse to a blinking light pattern that changes color every time. While the individual colors aren’t quite as rich and brilliant as on GE’s Colorite lights, they still look good, and we think that’s a fair trade-off for the versatility that the Color Choice lights provide. The Color Choice lights also work indoors or outdoors, although we recommend plugging in the control box someplace where it won’t get wet.

Photo: Michael Hession

The GE Color Choice lights come in two warm colors, red and yellow, and two cool colors, blue and green. They all produce bright, strong tones, although the green is slightly limey. In white mode, however, the lights alternate between warm and cool color temperatures—that is, the red and yellow bulbs turn into warm whites, while the blue and green bulbs turn into cool whites. This difference isn’t too noticeable unless you’re actively looking for it, but it does end up producing a radiant white that’s more neutral than the traditional warmth associated with Christmas lights. These lights are still plenty bright, but if you’re specifically looking for that classic rich incandescent tone, you might be disappointed.

These lights also come with eight different light settings that you can cycle through by pressing the button on the control box. Although it’s nice to have the option to make your lights blink steadily or randomly, or to alternate between colors and white lights, we found that not all of the settings were as good as we had hoped. The pulsating lights in particular exhibited a stark and sudden jump in that moment between dim and all the way off, as if the designers couldn’t quite program the lights to draw their energy down with enough subtlety or sensitivity. As with the light colors, this is largely a symptom of the GE Color Choice lights trying to do too much all at once, but if you’re interested in these features, the Color Choice lights are by far the best option available.

You can remove the control box to expose a rounded dual-tip coaxial cable, which lets you combine multiple Color Choice string light sets and manage them all through a single control box so that all the lights remain in sync. Photo: Michael Hession

The wires that connect the individual lights on the GE Color Choice strand are tightly wound and don’t get too tangled, giving them a nice durability. Unlike other Christmas lights we tested, these have a standard two-prong input on one end and a rounded dual-tip coaxial cable on the other. You can actually unscrew the control box and two-prong plug and separate them, which leaves you with a coaxial connection on both ends. This is so that you can combine multiple Color Choice string light sets and manage them all through a single control box to ensure that the lights remain in sync. This also means that you can easily replace the control box if it stops working, as all you have to do is buy another set of Color Choice lights and string up to four sets together. This was a problem we encountered in our tests—the control box short-circuited after we submerged it in water, even though the lights themselves still worked. It’s something to keep in mind if you want to hang your lights outside. As long as you plug them in somewhere so the control box stays dry, the lights themselves should have no problem weathering the elements.

The competition

The Christmas Designers 5mm Wide Angle Conical LED Christmas Lights were our previous pick for outdoor lights. The colors were slightly less brilliant than those of the 5 mm wide-angle lights from Christmas Lights Etc in our tests, and the wiring is thicker, but they’re otherwise nearly identical. If the Christmas Lights Etc 5 mm wide-angle outdoor lights are unavailable, or you find the Christmas Designers lights at a better price, they’re a great alternative.

We also used to recommend the Christmas Designers Incandescent Christmas Lights. However, the company no longer carries a warm white incandescent option. If you’re looking for multicolor or solid-single-color incandescents, they’re still a great choice.

Christmas Lights Etc also makes a “commercial” version of its outdoor 5 mm wide-angle lights. In our tests, these were somewhat dimmer—the yellow and orange lights were a bit dull, and Bridget Collins, the lighting supervisor at the Huntington Theatre Company, described the white lights as “wimpy”—but they were otherwise comparable.

We tested several white and multicolor sets from Home Accents Holiday, which Home Depot carries exclusively. The incandescent lights were fine but ultimately failed our durability test, leaving a large chunk of the string unlit after we submerged them in water overnight. The standard Home Accents Holiday Mini LED Lights relied on non-rectified lights that produced a nauseating flicker, especially when they moved. The Home Accents Holiday Smooth Mini Super Bright Constant On lights were indeed super bright, as their name suggests, but in a painfully glaring way; they also suffered from that LED blinkage problem. Overall, the construction and wiring on all of these lights was sloppy and shoddy, and they just looked bad.

We previously tested and dismissed GKI/Bethlehem’s LEDs, the multicolor LED mini lights and 5 mm wide-angle multicolor LEDs from Noma, the wide-angle LEDs from Christmas Light Source, and Brite Star clear incandescents. We’ve also looked into the larger C7 and C9 bulbs, but we ultimately decided not to review them in detail for this guide. If you’re interested in larger bulbs, we recommend looking at the empty-socket lines from Christmas Designers and Christmas Lights Etc, which are typically sold by the foot. If you just need to know what typical bulb sizes look like and what they’re called, this comparative image from PartyLights.com’s Bright Ideas blog will give you a sense of the common sizes.

Similarly, if you’re interested in cluster lights, we generally recommend sticking with a trusted retailer like Christmas Designers or Christmas Lights Etc due to the variances we’ve seen in LED light quality. The ones we tested were from Christmas Designers, and those bulbs had the same warm incandescent-like look as the company’s other LED lines.

What to look forward to

In recent years, some manufacturers have started selling Christmas-light systems that you can control via a smartphone. These typically offer a wide variety of pattern and color options, all remotely controlled. We can see the appeal—especially if you’d like to turn outdoor lights on and off remotely while you’re traveling, or if disconnecting your decorations means stepping out into the cold. But between higher costs, app problems, and little long-term reliability, we haven’t recommended any. Our advice, if you’re interested in smart-home capability for your lights, is to invest in a smart plug-in outlet such as the Wemo Mini or the iClever IC-BS06 outdoor switch.

We’re continuing the search, though, and we are currently testing the new Twinkly Wi-Fi–enabled LED string lights, which are distributed by Christmas Designers. “After three years of working with [Twinkly’s manufacturers], we’re finally ready to move into that product line, and we’ve been extremely excited about it,” the company’s Jason Woodward told us. “We’ve had tremendous feedback from customers, and we’re really excited to see where it’s going. The future of Christmas lighting will be, you no longer will buy a red set, a green set, a blue set, a multi set. You’re going to buy one light set like a Twinkly set, and it’s capable of 17 million different colors.” Stay tuned for an update with some test results.

Safety concerns

Thanks to a reader, we discovered that nearly all Christmas lights have lead. We researched this topic, though, and discovered that the dangers are minimal. Still, you can take a few steps to limit any exposure.

According to a 2008 study from Cornell University, lead is a relatively common component in the PVC plastic sheathing that encases wires. Jason Woodward of Christmas Designers writes in an article that trace amounts of lead can also be found in things such as extension cords, computer cords, batteries, and even some cosmetics. All of this explanation isn’t to justify lead’s existence in Christmas lights, but rather to add some context regarding its prevalence in many common household items (and things that people handle far more often than Christmas lights).

According to the Occupational Safety and Health Administration, lead is harmful only if inhaled or ingested. It is not absorbed through the skin, so merely touching or holding Christmas lights doesn’t pose a risk. But as Woodward writes, trace amounts of lead can be transferred to the hands, so “the primary risk of absorbing lead after handling Christmas lights is through eating after handling the lights.”

The solution is an easy one: Wash your hands after stringing up the lights, or wear gloves while putting them on. It’s also important to minimize any exposure that young children might have with the lights; wee folk absorb lead at a higher rate than adults, and they’re more likely to put their hands in their mouths, thus ingesting lead.

Still, if you feel the need to go fully lead-free with your lights, we found a Safe Baby Healthy Child article indicating that lead-free Christmas lights are sold at IKEA.

How to light a tree

You can find varying opinions on how many lights to use for your tree. In our interview, GE’s John Strainic suggested 100 lights per vertical foot. But 100 lights per foot strikes us as a lot, and we imagine that the result would be a particularly festive tree.

The box that the tested Brite Star lights came in goes a little lower, giving a number of 600 lights for an 8-foot tree (or 75 per foot). And this lighting calculator from Christmas Light Source indicates that 250 to 400 mini lights will light an 8-foot tree.

You have a couple of different ways to apply lights, but one method in particular gets a lot of praise. It involves putting the lights on from bottom to top, doing so vertically, going in and out as you move up. This technique puts the lights deep in the tree and creates depth and a warm interior. You can find more information from Real Simple. (If that approach sounds too radical, you can just do it the traditional way by circling the tree, working from bottom to top.)

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