A19 Light Bulbs

A19 light bulbs are the standard pear-shaped bulbs that have illuminated homes, offices, and businesses for over a century. The "A" designation indicates the arbitrary or standard bulb shape, while "19" refers to the diameter in eighths of an inch – so A19 bulbs are 19/8 inches (approximately 2.375 inches) in diameter. These are the familiar bulbs that fit standard medium base (E26) sockets found in table lamps, ceiling fixtures, wall sconces, and countless other residential and commercial applications.

The ubiquity of A19 bulbs means they're available in every lighting technology: traditional incandescent (though these have been largely phased out for general service due to efficiency regulations), halogen incandescent that meets efficiency standards, compact fluorescent (CFL), and LED. Each technology offers different trade-offs in energy efficiency, lifespan, light quality, dimming behavior, and cost. The massive market for A19 bulbs means competition keeps prices reasonable and selection extensive.

Incandescent A19 bulbs in standard configurations (40W, 60W, 75W, 100W for general service) have been phased out in the United States and many other countries due to energy efficiency regulations. However, specialty incandescent A19 bulbs remain available: rough service versions with reinforced filaments for high-vibration applications, shatter-resistant versions with safety coatings, appliance bulbs rated for high temperatures, three-way bulbs for lamps with three-way sockets, and various colored and decorative versions. These specialty configurations are exempt from the efficiency regulations that eliminated standard incandescent bulbs.

Halogen A19 bulbs use halogen technology in the familiar A19 shape, providing light quality nearly identical to traditional incandescent while meeting energy efficiency standards through improved efficacy. These bulbs work well as direct replacements for traditional incandescent in applications where the warm 2700K light, perfect CRI 100 color rendering, smooth dimming, and instant-on operation of incandescent technology are valued. Lifespan is typically 1,000-3,000 hours, considerably better than old-style incandescent but far less than CFL or LED.

LED A19 bulbs have become the dominant choice for most applications, offering 75-85% energy savings compared to incandescent, 15,000-25,000 hour lifespans, and instant-on operation. A 9-watt LED A19 provides light equivalent to a 60-watt incandescent while lasting 15-25 times longer. Early LED bulbs had issues with color quality, dimming compatibility, and appearance, but modern LED A19 bulbs have largely solved these problems. Quality LED A19 bulbs now offer warm 2700K color temperature, 80-90 CRI color rendering, smooth dimming with compatible dimmers, and attractive designs that look good in open fixtures.

Color temperature selection allows you to customize the ambiance. Warm white (2700K) mimics traditional incandescent and creates comfortable, inviting light suitable for living rooms, bedrooms, and hospitality settings. Soft white (3000K) provides slightly crisper white light that's still warm and welcoming, popular in kitchens and bathrooms. Bright white (3500K-4000K) delivers more energizing light appropriate for workspaces and task-oriented areas. Daylight (5000K-6500K) produces very white, alert light that some people prefer for reading or detailed work, though others find it too clinical for home use.

Specialty A19 configurations address specific needs: three-way bulbs for lamps with three-way sockets (typically 30/70/100W equivalent in LED), colored bulbs for decorative applications and seasonal lighting, smart bulbs with integrated WiFi or Bluetooth for app control and automation, bug lights with yellow coatings that don't attract insects, and various other specialized versions. The standard A19 form factor makes these specialty bulbs compatible with the millions of fixtures already using A19 sockets.

Common Wattage Equivalents: 40W, 60W, 75W, 100W (incandescent equivalent). LED versions typically use 5W-15W to achieve these outputs.

Base Type: Medium screw base (E26) - standard household socket

Available Technologies: LED (most efficient, 15,000-25,000 hours), halogen incandescent (efficient incandescent, 1,000-3,000 hours), CFL (efficient but being displaced by LED), specialty incandescent (rough service, shatter-resistant, appliance, three-way)