Understanding light bulb sizes can be confusing. However, choosing the right size and type for your needs greatly impacts both functionality and appearance. Balancing factors like brightness and fixture compatibility is crucial, as each choice comes with trade-offs. Considering these details ensures effective lighting and enhances your space’s look.
Most Popular Light Bulb Sizes (US and UK)
| BULB series | CODE | DIAMETER IN (Inches and mm) | LENGTHS IN (inches and mm) |
| A Series | A19 (US) or A6 (UK) | 60 mm 2.4 inches | 3.9 – 4.3 inches (99.06 – 110 mm) |
| B Series | B10 | 31.75 mm 1.3 inches | 3.5 – 4.4 inches (90 -113 mm) |
| C Series | C9 | 28.58 mm 1.1 inches | 3.5 – 3.9 inches (90 – 100 mm) |
| CA Series | CA10 | 31.75 mm 1.3 inches | 3.5 – 3.9 inches (90 – 100 mm) |
| R Series | R50 | 159 mm 6.3 inches | 3.4 inches (86 – 87 mm) |
| R Series | R63 | 200 mm 7.9 inches | 3.9 – 4.0 inches (100 – 102 mm) |
| R/BR Series | R80 | 254 mm 10 inches | 4.4 – 4.8 inches (112 – 118 mm) |
| PAR Series | PAR16 | 50.8 mm 2 inches | 2.0 – 2.2 inches (50 – 55 mm) |
| PAR Series | PAR20 | 63.5 mm 2.5 inches | 2.5 – 8.9 inches(64 -89 mm) |
| AR Series | PAR36 | 111 mm 4.4 inches | 2.3 – 2.6 inches (58 – 66 mm) |
| PAR Series | PAR36 | 120.65 mm 4.8 inches | 5.3 – 5.4 inches (134 – 136 mm) |
| MR Series | MR11 | 35 mm 1.4 inches | 1.5 – 1.7 inches (37 42 mm) |
| MR Series | MR16 | 50.8 mm 2 inches | 1.8 – 2.1 inches (45 – 53 mm) |
| G Series | G25 (US) or G80 (UK) | 80 mm 3.2 inches | 120 mm 4.7 inches |
| G Series | G30 (US) or G95 (UK) | 95 mm 3.7 inches | 140 mm 5.5 inches |
| G Series | G40 (US) or G125 (UK) | 125 mm 4.9 inches | 6.5 – 6.7 inches(165 – 170 mm) |
| T Series | T30 | 30 mm 1.2 inches | 8.9 – 11.8 inches (225 – 300 mm) |
| T Series | T45 | 45 mm 1.8 inches | 110 mm 4.3 inches |
| T Series | T5 | 16 mm 0.6 inches | 12.0 – 57.6 inches (305 -1463 mm) |
| T Series | T8 | 26 mm 1.0 inches | 13.0 – 48.0 inches (330 – 1220 mm) |
Light Bulb Sizes – Shapes, and Codes
A Series.
| Description | Measurement |
|---|---|
| Common Lengths | 3.9 – 4.3 inches (100 – 110 mm) |
| Diameter | 60 mm (2.3622 inches) |
| Light Bulb Code | A19 (US) or A60 (UK) |
| Diameter (1/8th inch) | 2 3/8″ (10/8 diameter) |
B/C/CA Series
| Category | B10 | C9 | CA10 |
|---|---|---|---|
| Common Lengths | 90 – 113 mm (3.5 – 4.4 inches) | 90 – 100 mm (3.5 – 3.9 inches) | 110 – 130 mm (4.3 – 5.1 inches) |
| Diameter | 31.75 mm (1.3 inches) | 28.58 mm (1.1 inches) | 31.75 mm (1.3 inches) |
| Diameter (1/8th inch) | 10/8 (1 1/4″) | 9/8 (1 1/8″) | 10/8 (1 1/4″) |
R and BR Series
| Category | R50 | R63 | R80 |
|---|---|---|---|
| Light Bulb Code | R50 | R63 | R80 |
| Common Lengths | 86 – 87 mm (3.4 inches) | 100 – 102 mm (3.9 – 4.0 inches) | 112 – 118 mm (4.4 – 4.6 inches) |
| Diameter | 159 mm (6.3 inches) | 200 mm (7.9 inches) | 254 mm (10 inches) |
| Diameter (1/8th inch) | 50/8 (6 1/4″) | 63/8 (7.86″) | 80/8 (10″) |
MR Series.
| Category | MR11 | MR16 |
|---|---|---|
| Light Bulb Code | MR11 | MR16 |
| Common Lengths | 50 – 55 mm (2.0 – 2.2 inches) | 64 – 89 mm (2.5 – 3.5 inches) |
| Diameter | 50.8 mm (2 inches) | 63.5 mm (2.5 inches) |
| Diameter (1/8th inch) | 16/8 (2″) | 20/8 (2.5″) |
G Series
| Category | G25 (US) / G80 (UK) | G30 (US) / G95 (UK) |
|---|---|---|
| Light Bulb Code | G25 (US) / G80 (UK) | G30 (US) / G95 (UK) |
| Common Lengths | 120 mm (4.7 inches) | 140 mm (5.5 inches) |
| Diameter | 80 mm (3.1 inches) | 95 mm (3.7 inches) |
| Diameter (1/8th inch) | 25/8 (3.14”) | 30/8 (3.70”) |
T Series
| Category | T30 | T45 |
|---|---|---|
| Light Bulb Code | T30 | T45 |
| Common Lengths | 225–300 mm (8.9–11.8 inches) | 110 mm (4.3 inches) |
| Diameter | 30 mm (1.2 inches) | 45 mm (1.8 inches) |
| Diameter (1/8th inch) | 1.18” | 1.77” |
AR and PAR Series
| Category | PAR16 | PAR20 |
|---|---|---|
| Light Bulb Code | PAR16 | PAR20 |
| Common Lengths | 50–55 mm (2.0–2.2 inches) | 64–89 mm (2.5–3.5 inches) |
| Diameter | 50.8 mm (2 inches) | 63.5 mm (2.5 inches) |
| Diameter (1/8th inch) | 16/8 (2″) | 20/8 (2.5″) |
Importance of Choosing the Right Light Bulb Size
Selecting the correct light bulb size is crucial for achieving the desired lighting effect and ensuring compatibility with your fixtures. On one hand, choosing the right size guarantees that the bulb fits perfectly and performs optimally. On the other hand, selecting the wrong size can lead to inadequate lighting or even damage your fixtures.
Balancing factors like bulb dimensions and fixture requirements is essential. By carefully considering these details, you enhance both the functionality and aesthetics of your space, ensuring that your lighting setup meets your needs effectively.
Common Light Bulb Sizes and Types
A-Series Bulbs (Standard Bulbs)
A-series bulbs are the most common and come in various sizes, with the A19 being the most popular for general use. While these bulbs offer versatility and are suitable for most fixtures, they may not always provide the specialized lighting effects needed for certain applications.
Choosing the right A-series bulb involves balancing general functionality with specific lighting requirements.
B-Series Bulbs (Bent Tip Bulbs)
B-series bulbs are often used in decorative fixtures and have a distinctive bent tip, adding an elegant touch to chandeliers and sconces.
Although they enhance visual appeal, they may not be ideal for tasks requiring bright, focused light. Therefore, it’s important to consider whether the aesthetic benefits outweigh the potential trade-offs in lighting performance.
C-Series Bulbs (Candle Bulbs)
C-series candle bulbs are designed to mimic the shape of a candle flame, making them ideal for accent lighting and chandeliers. Their charming appearance suits decorative purposes but may not offer the brightness needed for functional lighting. Balancing aesthetics with illumination needs is key when choosing C-series bulbs.
PAR-Series Bulbs (Parabolic Reflector)
PAR-series bulbs are known for their directional light and are commonly used in spotlighting and floodlights. While they excel at focusing light on specific areas, they might not be suitable for general room lighting. Carefully consider the trade-off between focused illumination and broader light distribution to meet your lighting goals.
Tips for Buying Light Bulbs
Where to Buy
Finding the right light bulb can be as simple as visiting your local hardware store or exploring online retailers. While physical stores allow you to see and compare bulbs in person, online shopping offers a wider selection and often better prices. Consider the trade-offs between immediate availability and variety when choosing your purchase method.
Checking for Quality
Look for reputable brands and check reviews to ensure you’re purchasing a high-quality bulb that lasts. Although higher-priced bulbs may seem like a greater investment, they often offer better performance and durability. Balancing cost with quality is essential, as a well-reviewed bulb can save you from frequent replacements and ensure optimal lighting performance.
FAQs
FAQ 1: What is the difference between A-series and PAR-series light bulbs?
Answer: A-series bulbs, like the A19, are standard bulbs designed for general lighting and come in various sizes. They are versatile and fit most fixtures. PAR-series bulbs, on the other hand, are parabolic reflector bulbs that focus light in a specific direction. They are ideal for spotlighting and floodlighting but may not be suitable for general illumination. The choice between them depends on whether you need broad, general lighting or concentrated, directional light.
FAQ 2: How do I determine the correct light bulb size for my fixture?
Answer: To determine the correct light bulb size for your fixture, first measure the diameter and length of the existing bulb or the socket’s dimensions. Refer to your fixture’s specifications or user manual for recommended bulb sizes. Ensure that the new bulb fits well and provides the appropriate light output for your needs. Balancing bulb dimensions with fixture requirements ensures compatibility and optimal performance.
FAQ 3: Are there any benefits to buying light bulbs online compared to in-store?
Answer: Buying light bulbs online offers several benefits, including a wider selection, often lower prices, and the convenience of shopping from home. However, in-store purchases allow you to see and compare bulbs in person, which can be helpful for ensuring fit and quality. Consider the trade-offs between immediate availability and broader choices when deciding where to buy your light bulbs.