Watts to Lumens Conversion Chart: Choosing the Right LED Lights for Any Project
There’s absolutely no denying it: LED lights are a good investment. Not only are they better for the planet, but they’re significantly better for your wallet. In fact, they can be six to seven times more energy efficient than incandescent light bulbs. But for many consumers, making the switch from incandescent, fluorescent or halogen to LED can be a bit confusing. Where we used to measure brightness based on watts — the higher the watts, the brighter the bulb — now we have a whole new set of parameters for which to choose our lights. These parameters dictate a bulb’s brightness, energy draw and annual operating cost.
Pro Tip: Shop with LED light retailers like Mills LED that tell you exactly which LEDs can be used to replace lights rated in watts. Look for “equivalent” ratings for easy replacement.
If you’ve just picked a bulb off the shelf for your project and installed it in your home or business only to find that it’s either far too bright or far too dim, then you’ll find this reference article handy. Instead of looking for wattage when shopping for lights, you need to get comfortable with lumens. Because here’s the thing: while previously brighter bulbs drew more energy (more watts), LED lights don’t require the same energy draw. Therefore, a 60-watt incandescent and a 6-watt LED light may be equally as bright as one another, but the LED bulb will draw much less energy.
What Are Lumens?
Before we dive into how to convert watts to lumens, let’s get down to the basics. In scientific terms, a lumen is a measurement of luminous flux (how much energy of light is emitted in all directions per second) equal to light emitted by a uniform point source of one candle intensity. In layman’s terms, that means that lumens measure the quantity of visible light emitted from a certain source, otherwise known as brightness.
The main reason we use lumens over watts when classifying LED lights is because LED bulbs are able to produce a much higher brightness output while drawing a lower wattage. Therefore, how many watts an LED light draws does not correlate with how bright or dim it may be. Basically, if you intend to make a total shift to LED lighting, then you should forget everything you know about brightness and light bulbs!
In 2012, the Federal Trade Commission (FTC) mandated that lighting manufacturers must indicate the lumens on the packaging, regardless of whether it contains an LED, an incandescent, a halogen or any other kind of light bulb. The goal, says the FTC, is to help the public get more comfortable with LED technology and to help consumers make better decisions to save money over time.
Lumens to Watts Conversion Chart
Let’s say you’ve used the same wattage in your warehouse high-bay lights for the past three decades, but you’re ready to switch to LEDs to save your company some extra money associated with operation, maintenance and replacement. It’s a smart choice. Where you might have once used a 400-watt metal halide, you can now get away with a 180-watt — that means lower operating costs and a longer lifespan — without compromising any brightness whatsoever.
Use the following lumens conversion chart or this handy watts to lumens calculator for more information on which lumen level you need to maintain a certain amount of brightness. The left column shows how many watts are used to achieve a certain lumen amount (middle column) while the right column shows how many watts are needed for the same amount of lumens when using an LED light. As you can see, LEDs require much less wattage for the same result.
The Color Temperature Factor
Understanding how much brightness a bulb emits is a key factor when designing a lighting scheme for a room, but it’s not the only factor. As you may have noticed when shopping for LED lights, there seem to be many more options and variations compared with conventional incandescent bulbs. In addition to a full spectrum of lumens, which helps you choose lights that emit the perfect amount of brightness for your unique needs, LED lights also come in different color temperatures and shapes so that you can customize the lighting to the environment.
What is color temperature? This specification, measured in Kelvins on a scale of 1,000 to 10,000, doesn’t have anything to do with brightness, but instead designates the color or appearance of the bulb. Temperatures in most commercial and residential LED light bulbs range from 2,200 (warm) to 6,500 (daylight). Choosing the right color temperature really comes down to preferences, but the number on the scale can affect how warm, inviting, calming or workspace-friendly your lights will be.
What About Dimmers?
Another thing you need to know before embarking on your LED light project is that dimmers don’t work the same way as they do with conventional light bulbs. You should know a little bit about dimmers in order to create a custom lighting environment that’s tailored to your individual needs as they fluctuate; dimmers can turn cool task lighting into soft accent lighting within a single fixture, making the light in even single-fixture rooms completely customizable. The most important thing to note is that not all LED bulbs work with dimmers, so if this is a feature you want, be sure to look for light bulbs marked as dimmable.
Choosing the Right LEDs for Any Room
Whether it’s your home, workspace or office, creating a lighting scheme that makes the environment more hospitable and enjoyable is an important part of the design process. We know that certain spaces require more brightness, while others should be a bit more subdued in the lighting department. But without watts, how do we know which bulbs to install where? Here’s some good advice.
The Right LED Lights at Home
Choosing the right lumen level for the room can be a challenge, but we’re here to help. Note that the suggested lumens are the total for the room or area, so you’ll obviously want to disperse light across various fixtures in each room. For the best results, think in lumens per square foot (measured in foot-candles) or square meter rather than lumens per bulb.
- Living Space —The living room is the perfect example of an environment where you should install dimmable LED lights so you can adjust the light from cozy accent lighting to brighter task lighting for cleaning, reading and working. Aim for a total brightness of between 2,000 and 5,000 lumens in a warmer color temp. Calculate about 20 lumens per square foot for the living room.
- Kitchen —The same goes for the kitchen; you need to be able to turn up the lights for food prep and dial them down when you’re having company and want to set a certain mood. Stick to a bright but not too bright lumen rating — between 4,000 and 10,000 lumens is usually sufficient, depending on the size.
- Home Office — What kind of work you do at home will determine how many lumens you need in the office. If your primary work is on the computer, stick to a middle-ground lumen rating. If you do a lot of reading, assembling, writing or drafting, then go for task-heavy brightness — between 4,000 and 6,000 lumens.
- Garage — Ambient lighting is less important here. What is important is brightness. Go for a higher brightness in the garage, somewhere between 10,000 and 13,000 lumens in a residential garage, depending on the size.
- Bathroom — We’re used to bright light in the bathroom (think of those dreadful incandescent bulbs usually found in public restrooms), but the key is finding a balance between bright and flattering lighting for getting ready. Choose a bright daylight bulb at around 5,000 lumens to strike a good balance. Between 70 and 80 foot-candles are usually needed in the bathroom.
- Walk-In Closet — Determining brightness of the walk-in closet is similar to that of the bathroom — you need a level that’s flattering but also task-oriented for getting dressed, doing your makeup and other applications. Opt for a warm white bulb at around 2,000 lumens.
The Right Commercial LED Lights
While similar to residential lights, commercial LED lights serve different purposes, and therefore we can’t use the same process in determining brightness in industrial or commercial facilities. Typically, you will want brighter light in commercial spaces where the primary objective is to increase productivity, safety and employee comfort.
- Warehouse — Warehouses are big, high-ceiling spaces typically illuminated by high-bay lights. We’d recommend about 50 lumens per square foot, which equals about 1,250,000 lumens for a 25,000-square-foot warehouse.
- Parking Lot — Parking lot and parking garage lighting are unique in that they must provide security and be able to perform well when faced with all sorts of weather, including moisture. Color temperature is usually somewhere on the middle of the spectrum (around 5,000 Kelvins) for such applications. You can use this calculator from the Lighting Research Center to determine lighting for your parking lot.
- Retail Setting — Unlike other commercial environments, stores, showrooms and galleries should have more subdued and ambient lighting — in other words, steer clear of any “harsh” lights that could create an abrasive, unwelcoming environment. To draw attention to certain products, wall art or areas of the store, consider using spot lighting or track lighting at a higher lumen. Because retail environments can vary so widely, it’s best to consult the experts when designing store lighting. For reference, a typical department store usually uses about 40 foot-candles.
- Classroom — Because students need adequate lighting for reading, writing, drawing and making projects, classroom lighting should be sufficiently bright. Like warehouses, classrooms should have about 40 or 50 lumens per square foot (foot-candles) for the best lighting level.
- Medical Facility — Doctor’s offices, hospitals, clinics and other medical environments will have a variety of different lighting needs in each building and room, so this is another instance where partnering with a pro is important to getting the right result within budget. Hallways, exam rooms and labs, for example, will require more brightness than waiting rooms.
- Greenhouse — Brightness is important in your greenhouse or agricultural facility because it, of course, affects how much light is supplied to the plant. Therefore, you need to choose brightness based on how much light is required by the things you’re growing.
Need more assistance? You can always contact us or request a quote for custom lighting advice. We’re available to help you find the right LED light solutions for your space, whether it’s a massive distribution center, a small boutique or a new home. We can even assist with projects like converting your gym or athletic facility, factory or farm to LED lighting so that you’ll save on energy bills and maintenance over time.