Understanding common household light bulb shapes, sizes, and styles is important whether you’re converting outdated incandescent fixtures into energy-efficient ones or using LED bulbs for new-construction applications. Every light bulb has identifying characteristics that are represented by a letter or series of letters and a number; these are known as light bulb codes. The letter or letters in a bulb code indicate either shape or special features such as reflector type. Numbers in a bulb code indicate size in millimeters or eighths of an inch. These codes will tell you if a bulb will fit in your fixture and if it’s the right shape.

For every light fixture or application, there’s going to be a specific bulb or light bulb shape that will fit best and provide the right type of light. If you understand bulb codes, it’s easy to look at a light fixture and know right away what kind of bulb you’ll need.

Let’s talk about light bulb groups, their bulb codes, and what applications those bulbs are typically used for.

Standard/arbitrary (A) bulbs are the most widely used and thought of when it comes to household lighting. These bulbs work well for a variety of applications, such as ceiling lights, lamps, vanity lights, kitchen lights, closet lights, porch light fixtures, and so many more.

Numbers in each code refer to the bulb’s diameter in one-eighths of an inch.

A15 bulb: 15/8 = 1-7/8″ diameter

A19 bulb: 19/8 = 2-3/8″ diameter

A21 bulb: 21/8 = 2-5/8″ diameter

A25 bulb: 25/8 = 3-1/8″ diameter

Most common base types:

Globe (G) bulbs have a full, round shape and are available in various sizes. They can be used for many applications throughout the home, such as foyer lights, kitchen lights, chandeliers, and ornamental fixtures. The most common type is the large G30 bulb, which is used in bathroom and makeup vanities.

Depending on the bulb, numbers in each code can refer to the bulb’s diameter in one-eighths of an inch or in millimeters.

G11 bulb: 11/8 = 1-3/8″ diameter

G14 bulb: 14/8 = 1-3/4″ diameter

G16/G50: 16/8 = 2″ diameter

G60: 60 millimeters = 2-3/8″ diameter

G25/G80: 80 millimeters = 3-9/64″ diameter

G30: 30/8 = 3-3/4″ diameter

Most common base types:

All of the bulbs in these groups resemble the shape of a candle flame and are often referred to as candle bulbs. Conical (C) bulbs are shaped like a cone. Conical angular (CA) bulbs are shaped like a cone but have a bent tip. Blunt-tip (B) bulbs are very similar to C-type bulbs but have more of a torpedo or bullet shape. These bulbs can be used in chandeliers, wall sconces, pendant lights, night lights, decorative light strands, holiday light strands, and other decorative home lighting applications.

Numbers in each code refer to the bulb’s diameter in one-eighths of an inch.

B10 bulb: 10/8 = 1-1/4″ diameter

CA10 bulb: 10/8 = 1-1/4″ diameter

C7 bulb: 7/8 = 7/8″ diameter

C9 bulb: 9/8 = 1-1/8″ diameter

C15 bulb: 15/8 = 1-7/8″ diameter

Most common base types:

BR stands for bulged reflector. Traditionally, the inside surface of an incandescent BR bulb is covered in reflector material that is used to gather and cast a wide beam of light away from the bulb. LED BR bulbs don’t require the reflector material. These bulbs can have a frosted, clear, or patterned dome-shaped lens that diffuses light and provides a gradual fade into nonilluminated areas. BR bulbs also produce less shadows when compared to PAR bulbs. They’re a bit longer than PAR bulbs and tend to protrude from light housings but are used in similar applications, such as track lights, recessed lights, display lights, or can lights.

BR20 bulbs are often referred to as R20 but have the same characteristics of other BR bulb types. The R stands for reflector.

Numbers in each code refer to the bulb’s diameter in one-eighths of an inch.

BR20/R20 bulb: 20/8 = 2-1/2″ diameter

BR30 bulb: 30/8 = 3-3/4″ diameter

BR40 bulb: 40/8 = 5″ diameter

Most common base type:

Multifaceted reflector (MR) bulbs are small in size with a reflective, faceted interior. The facets create a concentrated beam of light that can be displayed in a narrow spot or wide flood beam pattern. Because of the directional light they provide, MR LED bulbs don’t require the facets but often still have them. These bulbs are available in a variety of colors and can be used for many applications, including track lighting, recessed lighting, desk lights, and display case lighting. Many MR bulbs operate on low-voltage wiring systems, which makes them great for outdoor and landscape applications such as driveway lights, path lights, gazebo lights, paver lights, and malibu lights that have weatherproof housings.

Numbers in each code refer to the bulb’s diameter in one-eighths of an inch.

MR11 bulb: 11/8 = 1-3/8″ diameter

MR16 bulb: 16/8 = 2″ diameter

Most common base types:

Tubular (T) bulbs come in a variety of lengths and widths. Depending on their size, these bulbs can be used in applications ranging from chandeliers, wall sconces, and pendant lights to basement and garage troffer light fixtures.

Numbers in each code refer to the bulb’s diameter in one-eighths of an inch.

T7 bulb: 7/8 = 7/8″ diameter

T8 bulb: 8/8 = 1″ diameter

T10 bulb: 10/8 = 1-1/4″ diameter

T14 bulb: 14/8 = 1-3/4″ diameter

Most common base types:

Want to improve your yard? One of the easiest ways to make it more beautiful is to add outdoor lighting. These multi-functional decorations can both help brighten your property and let you use it round-the-clock and make it even more beautiful by adding some soft, highlighting illumination. While outdoor lighting used to involve substantial work, including running bulky and often-ugly electrical runs, today’s homeowners have a number of new technologies that can safely and permanently run electricity without breaking their bank or compromising on beauty. Here are a few of the great options available to homeowners today.

LED lights are more affordable than ever before, and come in a massive range of styles, colors, and can be utilized for nearly any purposes. Perhaps the best part about them is that they are so small that they use very little electricity, while still offering a considerable amount of light.

LED lights come in many different forms, including spotlights, rope lights, or individual bulbs, meaning you can apply them almost anywhere. Looking to illuminate your deck? Run a few strands of LED bulbs across the top for a mood-setting glow. Want to highlight the beauty of your garden? Install a few lights around your prized plants. The possibilities for installing LED lights are endless.

Pools have had lights for many years, but a modern pool light offers extra options that were never available before. Turn the water in your pool or hot tub a fun color, or cycle through different colors quickly with color-changing bulbs. Additionally, modern pool lights need far less electricity to run and can offer even brighter solutions than ever before. Plus, a pool light can help you stay safe at night by making sure you see the water at all times.

Pathway lights can offer a lovely dressing for your existing paths as well as help you avoid any potential trip hazards. If kids leave toys out on the path, you can avoid these obstacles with a few simple pathway lights. Some models of pathway lights are even solar powered, gathering sunlight during the day to power themselves and then turning on at night with a subtle glow.

Security lights can help shine light in pivotal spots of your home during darkness hours, such as near front-facing windows or your front door. Many of these lights are motion-activated and require very little work to install, but can flood an area with bright light to help you spot and keep away potential intruders. Other types of security lights stay on all night long and offer you the peace of mind of knowing your home is not shrouded in darkness that encourages illegal activity.

Local Dallas and Plano electrician with over 27 years of experience providing electrical repair and installation services, has reached a landmark in their service to the local community by performing their ten thousandth job for local homeowner, retired military veteran, and retired school district employee Mr. Frank Norwood.

As a thank you to Mr. Norwood for his loyal repeat business and a celebration of this huge milestone for the company, ElectricMan Inc. installed a new ceiling fan and ceiling fan rated brace kit in Mr. Norwood’s master bedroom at no charge.  Master electrician and Owner of ElectricMan Inc., Nick Schaeffer, said “We are very excited to have passed this milestone as a company, and are honored and happy to provide this complimentary service to Mr. Norwood, a gentleman who has given so much for this country and the community.”

ElectricMan Inc. is committed to providing the absolute best customer service and reliability in serving the local community’s electrical repair and installation needs.  In light of the current status of many businesses, for a local company to reach the landmark of 10,000 jobs certainly speaks to their character and the quality of service that they provide.

About ElectricMan Inc.

As electricians, energy efficiency is always at the forefront of our mission. Since heating and cooling account for nearly half your utility costs, we believe that it is our duty to help customers integrate efficient home practices that cut costs but not comfort. Now that the spring season is in full swing, make sure your home is a respite by installing ceiling fans throughout your home. Ceiling fans boast numerous benefits, all of which you will thoroughly enjoy throughout every season. With temperatures soon to be on the rise, you’ll want to act quickly before it’s sweltering.

There’s a common misconception that ceiling fans cool rooms, however, the truth is that they actually cool skin. Therefore, if you were to leave a fan on in a room where nobody is present, you would only waste energy. To get the most out of your ceiling fan, you need to actually be in the room for the wind chill effect to work.

just 15 years ago. I wonder if any of the attendees at COMDEX thought to themselves “One day, I can cook my steak with the help of a tiny glowing tool that changes colors when my meat is cooked to perfection.” Probably not. Thankfully Sharper Image did, so now you can cook your steak and monitor it from your smart phone.