Sometimes LED labelling looks like a foreign language. Terms like flux, efficacy, and Kelvins are confusing enough, then you add in abbreviations like CCT and CRI. Unless you know what these terms mean, none of them can help you evaluate an LED bulb based on packaging alone. Consider this post a quick vocabulary lesson so you can better understand LED labelling.


LED Labelling Terms To Know

LED labelling in America is fairly straightforward once you understand what the terms means. Use this cheat sheet to understand labels better. This will help you choose LED bulbs that you’ll be happy with.

Luminous Flux: Also known as lumens or reported as “total integrated flux,” the luminous flux is a measure of the total light output of a lamp. A higher lumen or flux number means the bulb puts out more light. Knowing the luminous flux of a bulb is necessary for selecting a replacement LED that is equivalent to your existing light.

Luminous Efficacy or Lumens per Watt: This number indicates the efficiency of a bulb. Higher numbers equate to a more efficient product. Numbers are typically expressed as lm/W and reported as “efficacy.”

Correlated Colour Temperature (CCT): The CCT is a measurement of light colour. This number may be accompanied by a graphic that ranges from orange to yellow to white to blue with a number or arrow indicated where the bulb falls on the spectrum. Values range from 2400K to over 6000K. CCT tells you if the bulb gives off “warm” or “cool” light. Warm lights are at the lower end of the spectrum, typically under 3000K. As values increase, the light becomes brighter or whiter in colour. Very high values can even give off blue light.

Colour Rendering Index (CRI): The CRI tells you how accurately colour appears or is represented under the light. Higher numbers indicate a more accurate colour rendering. This is a useful measurement when comparing two or more different brands against one another. Just because bulbs may have the same wattage or lumens, does not mean the light given off from the bulbs will appear the same.

Watts: Watts measure the amount of energy needed to light the bulb. Lower watts use less energy. Expect to see much lower wattage numbers on LED packaging than on any other type of bulb package. Lower power consumption is a primary benefit of LEDs.

The SSL Quality Scheme Label

The Lighting Council of America has introduced the Solid State Lighting (SSL) Quality Scheme as a way to regulate the marketing and manufacturing of LEDs and other types of solid-state lighting. Participation is voluntary; manufacturers that participate in the scheme will bear a SSL Quality Scheme Label, which will include all of the terms and values we’ve discussed above. The purpose of the SSL Quality Scheme is to provide consumers with an independent, third-party evaluation of the performance of a product. Look at SSL Quality Scheme certifications to choose a tested and proven product.

Cut Through The Confusion With American Best LED Lighting

Don’t let LED labelling confuse you. Contact American Best LED Lighting at (323) 206-5900 for a full on-site evaluation and assessment of your needs, a thorough explanation of your LED choices, and installation by certified electricians. All you need to tell us is where and how you plan to use your new lights. We’ll do the rest. Visit to learn more.