Every type of light bulb has a different average rated life. In general, incandescent bulbs have a shorter lifespan than CFLs, while LEDs will typically outlast both of them

Average rated life

In Australia, manufacturers are required to show this as the 'average rated life’, which is the industry standard rating system, and which shows the average number of hours that a given type of bulb produced light during testing. For halogens and CFLs this represents the amount of time until they stop working. For LEDs, this time is the point at which light output from the globe is 70% of its original rated value - this lifespan measurement is referred to as a light bulb's L70 rating

Color temperature is the color characteristic of light. Color temperature can change the feel or mood of any room or work space in any multifamily, commercial, or institutional setting. Purchasing light bulbs with the right color temperature can help you create consistent and inviting lighting effects in any room.

dimmable: Able to be dimmed; able to have illumination decreased in brightness

Globe Base

Modern Light Bulbs: Shapes And Sizes

These are the eight most common light bulb shapes you’ll find in your home:

• Arbitrary (A)
• Bulged Reflector (BR)
• Candle (C)
• Globe (G)
• Quartz Reflector Lamp (MR)
• Parabolic Aluminized Reflector (PAR)
• Blown Reflector (R)
• Twist

It’s important to note that while these names are fairly common throughout the industry, there is no universal set of terms to describe the shape of a light bulb. For example, a compact fluorescent light bulb (CFL) will be described as a “twist” or “spiral” shaped bulb. Because of this, we recommend that you bring your old light bulb with you to the store so you can compare it with your new light bulb to ensure it’s the proper shape and size.

The following graphic should help to give you a better idea of what these bulb shapes look like:

Wattage (watts)