What Are Globe Lights? | Shape, Sizes & Safe Use

Globe lights are spherical bulbs or fixtures that cast soft, even light in every direction, most often used where the bulb itself is visible.

For the full breakdown, see our best 12V Light Globes guide.

The name describes the shape, not a brand. A globe light is any lamp or fixture built wholly or partly like a sphere, from small vanity bulbs to 5-inch patio string lights. That round form does more than look distinctive: it spreads illumination evenly rather than throwing a harsh beam, which makes globe lights a favorite for open-socket pendants, bathroom vanity bars, chandeliers, restaurant dining rooms, and outdoor string lights where the bulb sits fully exposed.

How Globe Light Sizes Work

Globe bulbs follow the same naming system as most bulb shapes. The letter “G” stands for globe, and the number after it tells you the diameter in eighths of an inch. That means G25 doesn’t indicate a model number but a physical size you can measure with a ruler.

• G16 — 2 inches wide, common in small vanity bars and mini pendants
• G25 — 3.125 inches, a standard size for bathroom and dining fixtures
• G30 — 3.75 inches, visible in chandeliers and open fixtures
• G40 — 5 inches, the classic patio and string-light bulb

Don’t confuse globe bulbs with GLS or golfball shapes, which look similar at a glance but carry different codes and dimensions. When a fixture lists a maximum size or wattage, stick to it: a replacement bulb must stay below the fixture’s wattage rating or you risk overheating the wiring.

Inside a Globe Light: Materials and Build

Globe lighting fixtures come in glass, plastic, or metal, and the sphere itself is sometimes fully enclosed, sometimes open, and sometimes cut off on one side to direct the light. The classic glass G40 patio bulb is what most people picture, but the same shape appears indoors in frosted vanity globes that soften the glare of bare bulbs.

Plastic has a clear advantage outdoors: shatterproof polycarbonate globes survive bumps, weather, and falls without spraying glass across a deck. The trade-off is that plastic can yellow or haze over years of direct sun, while glass keeps its clarity.

Using Globe Lights Outside Safely

Outdoor globe products need the right rating for the job. A UK safety report on a 25-bulb LED globe light chain found the product lacked IP44 outdoor protection, meaning moisture could reach live parts and create an electric-shock hazard. Before hanging any set, check that it is explicitly rated for outdoor use.

Manufacturer instructions for outdoor globe string lights repeat the same core rules:

• Unplug the lights before installation, maintenance, or changing a bulb
• Don’t exceed the product’s maximum connectable length
• Plug into an outlet suitable for outdoor use, protected from moisture
• Never immerse the plug or controller in water
• Swap bulbs only for the same type and wattage originally supplied

These steps prevent the two most common failures: overloading a chain past its rating and letting water reach an unprotected connection. For a more permanent setup, some homeowners choose low-voltage systems like the Philips Hue Festavia Globe Outdoor String Lights, which run on a plug-in power supply at lower voltage and reduce the risk of a serious shock.

If you’re choosing between models and want to see tested, practical recommendations for low-voltage setups, our roundup of the best 12v light globes covers the options worth your money.

Indoors or out, the fixture itself matters as much as the bulb. An outdoor-rated extension cord and a properly sealed socket keep moisture out; an indoor fixture hung outside invites trouble. For garages, workshops, and covered porches, match the fixture to the environment and keep bulb wattage under the label’s maximum.

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