What is lumen? Comparison of LED lumens and conventional bulbs

Think of lumens as the "new" way to understand the brightness of a lamp. Lumens = light output.

Simply put, lumens (expressed in lm) is a measure of the total amount of visible light (for the human eye) from a lamp or light source. The higher the lumen level, the "brighter" the light will appear.

In the past, we all bought 50W or 60W conventional bulbs or spotlights, hoping to achieve a certain level of brightness. This incorrectly links the power consumption (Watts) to the light output.

LED brings more light, less energy (Watts)

Using low-energy LED lights can achieve more light output with less power consumption. For example, a 6.5W LED light will provide a similar light output to a 50W halogen bulb. Under the same light output, the energy is reduced by 87%! When using LEDs, more energy is converted into light rather than heat. As technology advances, fewer watts will be used to produce more lumens, that is, more lumens per watt. Therefore, using watts as a brightness guide is no longer relevant.

Lumens-traditional and LED lights

To get the same light output as a 60W regular bulb, you will need an LED light with about 800-850 lumens. The lumen ratings of all integrated LED lights are clearly marked on the package and on the lamp holder. We also provide a conversion guide for the "old wattage" on the package, such as 11.5W LED = 60W regular.

The following is an approximate guide to help you determine the lumen rating of LED replacement lamps. (Click on power to view the products we provide)

Lumens per watt (lm / W)

This graph is a useful way to measure the efficacy of lighting products by dividing the total light output in lumens by the power usage in watts. You can think of this as similar to miles per gallon in a car, because higher lm/W means higher efficiency and lower operating costs compared to similar but less efficient models.

For example, an efficient Performance + backlight LED panel can provide 3500 lumens of light output with a power of 23 watts.

3500lm / 23 Watt = 152lm / Watt

In contrast, a popular but inefficient side-lit LED panel can provide 3,600 lumens for 45W.

3600lm / 45 Watt = 80lm / Watt

The 152lm/W panel is 51% cheaper than the 80lm/W panel.

We recommend that you take lm/W as one of the primary considerations when choosing an LED panel.

Lumens and useful lumens

For non-directional bulbs such as globes, golf balls or candles, the total lumen output in all directions will be calculated. When using directional bulbs such as GU10 spotlights, light will be emitted in multiple directions, some of which (overflow and leakage) may be useless, but it is included in the total lumen level.

In order to make comparisons fairer and easier, the European Union recently introduced a "useful lumen" rating. This is a measurement of the useful light emitted in a standard 90 degree cone (see image). The "useful lumens" rating is usually lower than the total lumens output, but is more relevant to spotlight bulbs, where useful light is focused forward.

How many lumens do I need?

There is no definite answer-it will depend on many factors, including: room size and shape, ceiling height, color scheme, type of lamps and accessories, task area and user needs.

As a basic guide; below are the lumens per square meter (10.76 square feet) required for different room settings. In many cases, general lighting and task lighting will need to be mixed.