Understanding Watts vs. Lumens for Home Lighting

Packages of light bulbs
New regulations will soon change the labeling of light bulbs.

There have been some major changes in lighting in recent years due to the introduction of energy efficient CFL and LED bulbs. Familiar old incandescent bulbs are becoming a thing of the past, as both their energy-hogging habits and their “wattage” rating become obsolete. In their places will be high efficiency bulbs with a much more accurate “lumens” rating. Here’s a handy guide to help you understand the difference and navigate the changes.

Watts vs. Lumens

To start with, what’s the difference between a watt and a lumen?


Watt label on light bulb package
Watts measure electricity.

Watts are a measurement of how much electricity something uses. It actually has nothing to do with how bright a bulb is, but incandescent bulbs are so similar that when we bought a 100-watt incandescent light bulb, we had a general idea of how bright it would be.

With newer types of bulbs, it takes far fewer watts to create just as much light, so wattage ratings are no longer very useful. Each type of bulb is different, and the whole idea is to develop bulbs that use fewer watts to make more light.


Lumens, on the other hand, actually measure the amount of light being put out by the bulb. Lumens are a much more accurate measurement, because it tells you how the light actually performs, regardless of the source that produced it.

One lumen is approximately equal to the amount of light put out by one birthday candle that’s one foot away from you. To help you get an idea of the lumen scale, a standard 60-watt bulb puts out around 750-850 lumens of light. If you’re choosing bulbs for task lighting, look for bulbs with 1000 lumens or more.

Light bulb packages showing lumens ratings
Lumens actually measure light output.

Lumens Per Watt Rating

Like miles-per-gallon in a car, the lumens-per-watt rating measures how much light that particular bulb produces per watt of power used, which tells you how energy efficient it is. Under the new system, when shopping for a light bulb, you should first look for the bulbs that produce the number of lumens you need.

Once you know the right brightness, you can then look at the lumens-per-watt rating to find the bulb that’s most energy efficient. The lumens-per-watt rating is an average, since light bulbs become less efficient as they age.

Goodbye Incandescents!

Incandescents light bulbs
Under the new energy standards, don’t expect to see incandescent bulbs on the shelves much longer. They don’t measure up to the new efficiency standards and will be phased out over time. Incandescent bulbs produce around 20 lumens per watt, while some of the newer LED bulbs pack a whopping 100 lumens per watt or more!

Energy Star Bulbs

If you’re not into fine print, one easy way to choose light bulbs is to look for the Energy Star rating. To qualify for Energy Star, light bulbs must meet certain lumens-per-watt standards. Here’s a handy chart to help you understand how watts and lumens relate to each other under the Energy Star system:

Watts (energy usage) Lumens (light output)
25 200
35 325
40 450
60 800
75 1100
100 1600
125 2000
150 2600

Further Information


  1. Current LED and CFL bulbs are still very crude and poor in quality compared to incandescent bulbs. In addition, lumens listed for bulbs appear to worthless in comparing bulbs. I have a 65W BR30 incandescent indoor flood with a 485 lumen brightness listed which is just as bright as a 60W incandescent bulb (which I would expect) but has a listed brightness of 850 lumens. When I bought a LED flood of 800 lumens (supposedly a 65W replacement, it was considerably brighter than my other 65W incandescent bulbs. Not only that, this supposedly dimable LED flood light was still much brighter and the lowest dim setting than all of the incandescent flood lights. How can consumers make accurate decisions with such lousy markings?

    • You are probably having trouble because you don’t understand color temperatures. Incandescents have a warm color temperature (2700 to 3000 kelvin) while LEDs and florescents normally produce cooler color temperatures (5000k+). Warmer temperatures are closer to candlelight, sunrise, and sunset while cooler temperatures are closer to daylight and pure white. The issue is that between a warm bulb and a cool bulb of equal lumens, the cool bulb will APPEAR to be brighter because of how humans PERCEIVE warm and cool color temperatures. The lumen scale is based on the actual light output, not on what different species of plant and animal life perceive the light output to be. Understanding this you can actually save a little by using dimmer (lower lumen) cool light bulbs when replacing existing incandescents.

      • Thanks for sharing your thoughts with the Today’s Homeowner community!
        TH community members helping other TH community members — we love it. 🙂

  2. need lights for my dogs (similar to a kennel set up) that spend a lot more time inside versus outside due to the weather. I need lights that will provide as close to sunshine as possible to prevent health problems.

  3. I recently installed four low profile LED fixtures in a customers basement. The ceiling was low and they worked well, nice light and came on immediaitatly . The customer also bought a LED hi hat for over the stairs.The probllem is there is a delay. The manufacture says that a three second delay is exceptable. I don’t think a three second delay is except able over a staircase but thats just me. I believe we have a way to go before all the glitches are ironed out.

  4. It sure would be helpful to have a chart available to compare watts to lumen. Untill the consumer gets familiar with the changing of everyday light bulbs. Right now I know that a 100 watt is what I need for a certain job. If the salesmen would tell me to just use a 1600 lumen new led bulb I would have absolute no idea if that would give me the equivalent amount of lighting. The charts I am thinking of could be hanging at the light-bulb department at stores were you can just take one with you home . This is my 5cents worth of suggestion. Thanks for giving me the opportunity to suggest this. Heinz

  5. I want to replace a large ceiling fixture of four (4) 40 watt T-12 (48″) bright white flourescent lamps with an LED fixture which I have not yet selected. My question: how many lumens do I need from my new LED fixture to match the brightness of the existing fixture?

  6. Great article! I wondered about lumen selection when I am on a paved trail for bicycles and am caught out in the dark by not preparing for quicker sunsets. Thanks!

  7. Great article, thank you for the information. The only thing I don’t see mentioned, and it may be in another article, is the color temperature. An 800 Lumen LED with a color temp of 2,700k (warm white) will not APPEAR as bright as the same rated bulb with a 3,800k, or higher, Daylight bulb. The lumens are the same, but your eyes perceive it differently.

    Also of note is that the color of the light from an LED bulb is someone’s idea of what that color should look like. It is not an integral part of the bulb as it is in an incandescent bulb. The color will look a little funny until you get used to it. The warm white may look too orangy, and the daylight may look too blue-white.

  8. When a socket states use no more then a 75 watt bulb can a energy saving bulb with a higher lumens be used if it states 15w. I was told the watts on the socket was for fire safety for the current being used not for the light being produced. So a 60w bulb produces an average of 800 lumens can I use a 1180 lumens energy saving bulb if it states it uses 15w.

    Thank you.

    Ken Dinsmore

  9. I have a 65w bulb in a 6 inch can fixture, that is rated at 1810 lumens. The box with the identical spare bulb (last one) gives the wattage and lumens. I was looking for replacements, and the only incandescent replacements I can find/only 60 watt say 530 lumens. The 10 year old bulb I have left has a $1.98 sticker on it. The fluorescent (CFL) PAR 30 bulbs costs $5.99 each and say 530 lumens/60W equivalent using and the CFL says 60w using only 15 watts, same lumens. I bought one each and tried it out. I have two light meters and both showed the old 65W bulb puts out nearly 1800 lumens, the new 60w incandescent rated at 530 puts out 410 and the CFL but after “warming up” for ten minutes reaches 280. I didn’t try an LED, the equivalent costs $49 each. Using cfls, I would have to install six more fixtures to get the same light level. Thus I go from one 65w (using 65 watts) to 7 fixtures with CFLs, each using 15 watts or 105 watts total to get the same light level. How is this saving electricity??? I know this is EPA mandated and I wrote them, and they answered that I don’t need that much light!

  10. Robert Stacy, that is very interesting. I’ve got some old bulbs at home. I think I’m going to have to check the boxes to see if they list lumens. In the mean time, if they’ll fit the can, you probably want the CFL that is a 100 equivalent. That should give you the correct lumens…..

  11. Here’s a fact that few would dispute: For quality of lighting, nothing beats an incandescent bulb. We got conned by cfls…the color they produce is not flattering to skin tone and the worst thing is that when they die (often much sooner then the *years* they are supposed to last) you end up with toxic waste because of the mercury in them. It’s illegal to throw them in the trash, and none of the retailers that are so happy to sell them will take the dead ones. Nice. Let’s hope led bulbs end up being better.

  12. Hi, can you help me on this?

    I use ceiling light for reading and doing work. What wattage light do I need? If the ceiling light has 3 connected in series down light, what should be the wattage for each down light? I refer to energy savings bulb.


  13. I think what the article fails to make clear is that watts and lumens aren’t like miles and kilometers. It isn’t simply two units for the same thing.

    Watts were an easy way to classify incandescent lamps since there were no other and it required basic and cheap electrician equipment to measure. In fact Watts is NOT a measurement of light, its a measurement of power used.

    With the arrival of many different kinds of light sources using a variety of powers (watts) and with different light outputs, the industry was forced to make more clear how much LIGHT that lamp would produce. That is where lumens come in. So the best would be if since beginning lamps were measured in lumens, which would be also more accurate.

    Some people are asking about different colours produce different sensation of light. To put it simply:

    Lumens is how much light your lamp puts out, consequently the space that it will illuminate.

    The colour or to put more accurately the temperature is the intensity of your light. up to ~3500K is warm white, not so intense and comfortable for living. ~4000-4500K is cool white. Much more intense and looking brighter, good for situations where u need more light, such as reading but it’s not relaxing. As a comparison, your sunny midday is about ~6000K equivalent and on sunny days you can feel its really bright and need sunglasses (too intense and not comfortable).

    • Nancy,
      The “K” Willian is referring to stands for “Kelvin”. It is a temperature scale used to measure the color of light. In light bulbs the higher the Kelvin temperature, the whiter the color of the light.

  14. In all the talk about lumens & watts we are kind of forgetting about HEAT. In the incandescent light world (watt world) incandescent lights produce lots of heat. With that being said,the answer to an earlier thread question why are standard light sockets rated in Max. Watts? If you install a 100 watt incandescent bulb in a socket rated for a 25 watt incandescent bulb you are literally “baking” the socket & the wiring and anything else near the bulb.

    • Tom,
      Good point! In the days when incandescent bulbs were the only choice for socket type light fixtures, it was a given that a certain watt bulb would give off a certain amount of heat. It’s not the gauge of the wires that determines the rated wattage maximum in most light fixtures, but the amount of heat the fixture and surrounding materials will be exposed to. CFLs and LEDs produce much less heat per watt, which is why you can use a brighter bulb in the fixture.

  15. Distance would also have an effect on lumens too. As a photographer I have a light meter but I would like to understand how to measure the proper illumination for viewing an image compared to my color balanced monitor. I understand the color temperature and even that 2000 lumens is about ideal from what I’ve read but I just don’t understand the disaptance to have the light source from the image in order to have the proper density or lumens. Anyone be able to tell me in photography terms for my light meter like ISO 100, 1 sec f.8.0. Thanks!

  16. Help!
    I have had 2 x 150W normal traditional domestic bulbs lighting a Garage/ DIY workshop measuring 8.5m x3.5m x2.5m high. I cannot get 150W bulbs anywhere. Are the not made anymore? What type/power/lumens can I use to give the same light. Baffled by all the jargon.

  17. Bob;
    Per the article, you need to look at the lumens (measure of light output) your old 150W bulb produced, and then find a new bulb with comparable lumen output. Most likely the new bulb will require a lot less than 150W power to output the same amount of lumens.

  18. I understand that lumen is a measure of the total light output of a bulb. How can I compare the same total lumen output of an omnidirectional bulb to a floodlight bulb? Are all the lumens of the floodlight bulb concentrated in the floodlight angle? That would make the floodlight intensity higher.

    Thank you for your answer.


  19. Hello Today’s Homeowner!

    I have a dining room chandelier. It has (5) incandescent bulbs.

    Question 1: Does (5) ea. 200 lumens LED bulbs equal 1000 lumens?

    Question 2: Or if I want 1000 lumens of brightness do I need (5) 1000 lumen bulbs?


  20. I have a ceiling light with 8 sockets. I want to have just 150 watts (old wattage) maximum light.The bulbs must be candle and pearl/opaque with standard bayonet fittings. What bulb should I go for – or will I need to fit a dimmer switch?

  21. In reply to Mr Crombie, there are plenty of options. B&Q sell the (non-dimmable) Diall Bayonet Cap (B22) 2W LED Filament Candle Light Bulb. Neat and pretty, but not cheap at £5.
    It’s costing me a fortune to switch to ‘low energy’ lighting. For example, a single 150w bulb in my office with a diffuser and dimmer, in constant use for 20+ years (never need to change the bulb) and costing in total £8, would need to be replaced by a 3-light fitting for 3 x 6w LED candles and a new low-load dimmer, all costing £80. Of course, with less heat given off by the ‘low energy’ bulbs, my central heating system will have to work harder: there is no energy saving when lights are inside the house and no recouping of the outlay. We have to comply with the EU idiots’ laws, but will they offer compensation for the needless expense? I estimate £2,000 by the time I’ve finished.

  22. Where is the best place for me to purchase Aluminum Recessed cans for LED lights and LED fixtures? I need 47 with the following: greater than 1600 Watts, 1600 or more Lumens, at least 4000K, Dimmable, screw in sockets A19 (medium). Thanks.


  23. Hi

    We have an angled ceiling en-suite bathroom which is being built. We do not want spots on the sloping part of the ceiling (unfortunately 85% of the room!) and instead would prefer to have a false flat ceiling installed at a height of 2400mm (i.e. the last 15% of the room width) where we can install recessed spots which can be tilted back towards rest of the room which is c. 2m.

    I know at 2400mm we are above the minimum height requirements for IP rated lights, but since part of it will be above the shower (and the room is small and likely to be steamy) we would prefer appropriately IP rated lights.

    Best solutions?

  24. I didnt see a referrence to light spectrum, the “color” of light eg; warm white, daylight, soft white, etc.
    This is just as important as intensity or wattage. It depends on personal preference when choosing color. I prefer bright white or sunlight for all lighting. Others might prefer warm or soft white for room lighting to create the desired effect of a particular decor. Dimmable bright white LED’s can be turned down or up, (intensity) depending on situation. See wavelength below; Wikipedia has good information on visible light spectrom and definition of angstrom, 1/f=Angs where f is frequency
    Violet: 3800 – 4500 Angstrom
    Indigo: 4200 – 4500 Angstrom
    Blue: 4500 – 4950 Angstrom
    Green: 4950 – 5700 Angstrom
    Yellow: 5700 – 5900 Angstrom
    Orange: 5900 – 6200 Angstrom
    Red: 6200 – 7500 Angstrom
    Read more at http://www.ibuzzle.com/articles/wavelength-of-visible-light.html or use google.

  25. So, I’m looking for a 500w (old rating) flood light for a swimming pool light. They never had any sort of Lumen rating on them so how am I to know how many lumens to look for. There must be some sort of chart somewhere to convert between the two. Yes, I realize the wattage is a power rating, but that’s all we used to have to go on. So am I looking for a 6000+ lumen flood light?

  26. Hi. I was reading about the maximum performance of different light sources. In all they mentioned as absolute maximum for a wavelength of 555nm (green ) value of 681 lm / W . However I could not find what is the maximum theoretical equivalence for white light, that is, one that contains all the colors of the light spectrum , or at least, equal amount of red, green and blue. Thanks for answering.

  27. Thank you for a clear-cut explanation of Lumens vs. Watts. In the market for an LED light kit and I had no clue how to compare the amount of light a lumen produced. Very helpful…Thanks!!

  28. But what about the light fixture that states 65watt maximum? Can I use higher lumen bulb( 75w equivalent ) since consume less energy ?

  29. So no incandescent light bulbs so I guess people won’t mind saving up a couple of days of work to buy a few bulbs?Bleeding money the lot of us it seems.

  30. Stores sell eqivalent 100 watt bulbs that are LED’s. The warm bulbs and the cool bulbs all say 1600 lumens but the cool ones light the room much greater! How can they be the same lumens?
    Also the old 100 watt soft white bulbs put out 2300 lumens of light and they have the gall to say the LED bulb is equivalent putting out 1600 lumens. The old bulb put out almost 50% more light!!!

    • The lumens are correct, they’re a scientific measure of the actual light output. The issue is that humans perceive cool light to be brighter than warm. In other words, it’s your eyes, not the bulbs.

  31. Mike’s complaint about the price, while common among those who fear change, are way off the mark. For a bulb that puts out the equivalent amount of light, an incandescent bulb has a life of 1,000 hours, a florescent (CFL) has a life of 10,000 hours, and an LED a life of 25,000 hours. An LED is not going to cost 25 times the price on an incandescent bulb, in fact, if you have a Dollar Tree near you or your willing to order a case of them at a time from them online you can purchase a typical bulb for, you guessed it, $1.00 apiece. They don’t have but a couple of options, but it’s a standard bulb and it’s what we use all over the house. The other plus is I couldn’t tell you the last time I had to change a light bulb except for the hood over the oven, and next time I’m looking for an LED for that one too. LED’s are really worth the extra dollars for places like outdoor flood lights where you have to climb a ladder which are a pain to change since you might go 10 years or more before changes and reading lamps since they don’t put out heat so close to you. Not to mention, if you have a home that uses a lot of lighting there’s a big energy saving, which coupled with the longevity can save money.

  32. Why have 100 watt equivalent light bulbs been reduced in brightness? The old 100 watt light bulbs were rated at 1700-1750 lumens. The new replacement bulbs seem to be rated at 1600 lumens. which is a loss in brightness at the same color temperature. I use to be able to get 100 watt daylight bulbs with 1700 to 1750 lumens now I can only get cfl 26 watt bulbs with 1690 lumens. My question is WHY?? I expect an answer!!

    • Hi, David,
      That’s a good question, and it’s best answered by light bulb manufacturers — they made the decision. 🙂
      Take care.

  33. I am afraid of an electrical fire if I pick a bulb and I don’t know if it is too big for a circuit or appliance. Can you help me?

    • Hi, Margaret! Totally get it — safety first.
      Your best bet is to read the product manual that came with the light fixture or appliance to determine which bulb to purchase.
      If you no longer have the product manual, but have the brand and model number, you can usually find the product manual online. Just run an internet search for it.
      If neither of these options work, it’s a good idea to call an electrician.
      Happy home improving!


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