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Convert Lumens To Watts And Watts To Lumens The Right Way

    Nothing’s ever simple, is it? Is there a fantastic new(ish) type of lighting that can save us money on our energy bills and give us articulate control over the ambiance in our homes? Yes, LED lighting.

    Can we make a straight swap for LEDs from our now defunct halogen bulbs? Not quite, at least not without engaging in a bit of math!

    Convert Lumens To Watts And Watts To Lumens The Right Way

    It’s not the voltage that’s an issue (on that front, it is pretty much a straight switch), it’s the way in which brightness is measured.

    See, with halogen lighting, it’s the wattage that signifies the luminosity of a bulb, but with the new king of home lighting, you need to keep an eye out for the aptly named unit, lumens.

    The reason this has caused such a kerfuffle is that people who want to match the luminosity of their current halogen setup don’t know which LED bulbs are up to the job, which is why I’ve composed this guide.

    Stick with me, and the halogen-to-LED transition will be totally pain-free!

    The Lumens To Watts Conversion

    In this article, I’ll be giving you the lowdown on this tricky conversion and explaining why lumens are an essential part of the exchange process.

    After all, what was so wrong with watts that we had to flip the system with a new unit?

    Watt-Lumen Conversion: When Life Gives You Lumens

    In the age of halogen bulbs, picking a brightness was simple and stress-free. All you had to do was check out the wattage. The higher the wattage, the brighter it would be; the lower the wattage, the dimmer it would be.

    This was because, for the halogen blueprint, the wattage genuinely did a great job in communicating the brightness.

    Not only did this make initial bulb selection very intuitive, it also meant that replacing that bulb was a total breeze. Did your 60 watt bulb kick the bucket? No worries, grab another from the store and you’re golden!

    With LEDs, on the other hand, although watts are still an essential measurement that indicates the power consumption of a light, they’re no longer the only indicator of brightness. Rather, watts only tell part of the story when it comes to the luminosity of an LED bulb.

    There are simply too many other variables involved in LED technology that can alter brightness. For instance, two LED bulbs with the exact same wattage can have extremely different levels of luminosity, but why is this the case?

    Well, it mostly comes down to the quality of components. In LED technology, there is more space for variation in this department.

    Those with lower quality components won’t be as bright as those made with the good stuff, even if they were both rated for, say… 5 watts.

    Just What Are Lumens Anyway?

    Lumens are a unit of measurement that expresses the degree of luminous flux emitted by a light source. While watts refer to overall power consumption, lumens – written “lm” – refer to the power of the visible light emitted per second.

    Although it’s a little irritating that we have to familiarize ourselves with this unit in order to capitalize on all the epic gains LEDs bring to the table, lumens are actually a very helpful construction.

    The great thing about lumens is that they allow us to compare different lighting formats accurately; lumens are universal.

    It doesn’t matter what technology you’re talking about or the efficiency of the lights in question, lumens are a bridge unit that helps us make sense of everything.

    Lumens To Watts Converters

    If you’re not big on equations (I don’t blame you), there are a number of online automatic lumens-to-watts calculators you can use to get the job done in a pain-free manner.

    How To Use A Lumens To Watts Calculator

    ​Lumens To Watts

    To use these nifty calculators, you’ll have to first select the conversion you wish to make. Let’s say you have the lumens; all you have to do is select lumens from the drop-down menu.

    You’ll also have to select the type of bulb you wish to compare your prospective LED bulb with.

    For instance, if you currently have halogen bulbs, that’s what you’ll select from the list. You have to specify as the wattage will be different between lighting technologies.

    Next, you’d input the figures. If you’re starting with lumens, you’d type the lumen count into the given field.

    Then you can trigger the calculation and let the converter do the work for you.

    Watts To Lumens

    The reverse conversion follows the exact same principles, but you’d set the conversion type as watts to lumens before entering the key details into their corresponding fields.

    Keep in mind, though, that these converters may not always be absolutely correct, but they’ll absolutely be close enough for you to make the LED switch in your home.

    Lumens To Watts Conversion: A Table Reference

    To give you a good idea of what you’re working with when aiming to convert lumens to watts, let’s take a look at this table displaying a collection of approximations based on averages.

    It references standard halogen light bulbs, halogen lamp bulbs, energy savers, and, of course, LEDs.

    Lumens (lm)

    Halogen Light Bulb

    Halogen Lamp Bulb

    Energy-Saving Bulb


    230–270 25 watts 19 watts 6 watts 2–3 watts
    430–450 40 watts 35 watts 9 watts 4–6 watts
    730–800 60 watts 50 watts 13 watts 7–9 watts
    970–1100 75 watts 64 watts 19 watts 8–11 watts
    1380–1600 100 watts 84 watts 23 watts 12–14 watts
    1500–1800 120 watts 98 watts 32 watts 15–17 watts
    2000–2500 150 watts 122 watts 40 watts 18–23 watts

    Comparison Examples Using The Table

    Finding An Equivalent LED Light To Replace A 60 W Light Bulb

    If you’re starting out with a 60 watt halogen light bulb, direct your attention to its position on the table. It can be found in the second column on the third row down.

    To the left, you’ll see that it equates to 730–800 lumens, and to the far right, you’ll see that the LED equivalent would have a power rate of 7–9 watts.

    Finding An Equivalent LED For A 13 Watt Energy Saver

    Now let’s say you’re looking to replace your 13 watt energy saver with an LED to take those savings to the next level. This light is referenced in the third row down in the fourth column across.

    To the far left, you’ll see this light emits roughly 730–800 lumens, and to the right, you’ll see the LED equivalent has a power consumption of 7–9 watts.

    Watts To Lumens Conversion: A Table Reference

    Now let’s flip the system and take a look at another table, this time displaying the watts to lumens conversion, just in case you need it.


    Halogen Light Bulb

    Halogen Lamp Bulb

    Energy-Saving Bulb


    5 watts N/A N/A 180 lm 500 lm
    7 watts N/A N/A 290 lm 700 lm
    9 watts N/A N/A 400 lm 850 lm
    11 watts N/A N/A 530 lm 1200 lm
    14 watts N/A N/A 730 lm 1500 lm
    25 watts 230 lm 300 lm N/A N/A
    40 watts 430 lm 500 lm N/A N/A
    60 watts 730 lm 900 lm N/A N/A
    75 watts 970 lm 1200 lm N/A N/A
    100 watts 1380 lm 1700 lm N/A N/A

    As mentioned near the beginning of this article, the reason that we can’t rely solely on watts to express the luminosity of LEDs is that the quality of components has the bigger impact.

    With this in mind, it’s perfectly reasonable that they’ll get even brighter in the future as the technology is refined time and time again.

    Things To Remember About Converting Lumens To Watts

    Lumen Score Is Different To Beam Angle

    While understanding the luminance flux of a light is a great start, bear in mind that intensity and beam angle are completely different things, meaning lumens won’t give you the full picture in terms of how the light will spread throughout a space.

    LEDs Have A Lower Beam Angle

    Generally speaking, the beam angle of an LED light will be slightly lower than that of a halogen or incandescent bulb. In other words, the indirect lighting supplied by an LED will be dimmer. You can think of them as more focused light sources.

    To account for this, you may want to install a second LED to balance the spread of light across the room.

    Final Thoughts

    If you dive into the process of updating your bulbs before considering the difference between lumens and watts, you’ll most likely end up buying a far too bright LED that will fry yours and your guest’s corneas — not cool!

    Take everything we’ve discussed here into consideration, and you and your precious corneas will love a long happy life, and if you’re feeling unsure when shopping around, don’t hesitate to ask for help from someone who works in the store. They’ll be able to guide you through the conversion process.