Lumens Vs Watts Vs Candela Vs Lux

If you’re like most people, you have forgotten a lot of the terms and measurements discussed in your high school science classes. However, when it comes to lighting and light measurements, there are various terms that can be extremely useful to know. Unfortunately, these terms can also get really confusing. The four most important terms to know when it comes to measuring light are Lumens, Watts, Candela, and Lux.

In today’s guide, we will define these four terms and see how they compare to one another. Additionally, we will see how specific measurements of one unit of measurement compare to another. So, let’s get started!

What Are Lumens?

A Lumen is a unit of measurement of the perceived power of light, known as the luminous flux. Lumens measure the total quantity of visible light emitted by a particular source per unit of time. Unlike other forms of light measurement, Lumens are not related to the area the light covers or even the intensity of light. Instead, it is specifically concerned with the degree of visible light produced by a single source over time. Since Lumens fall within the International System of Units (SI), they are often listed on light bulbs and similar products.

What Are Watts?

A Watt is a unit of measurement in the International System of Units that quantifies the rate of energy transfer. In layman's terms, the Watt is a unit that measures the power generated or consumed by something. In the realm of lighting, Watts refers to the amount of power used by a given light source over one hour (known as a Watt-hour). For example, a 50 Watt light bulb that has been turned on for one hour has used 50 Watt-hours of energy.

What Is Candela?

For the average consumer, Candela may seem like a completely foreign term. However, it is extremely important for the measurement of visible light. Candela is the unit of luminous intensity. In other words, we use units of Candela to measure the power or intensity of light produced by a single light source in a specific direction. This unit of measurement also falls within the International System of Units and gets its name from the traditional wax candle, as one candle produces roughly one Candela of luminous intensity.

What Is Lux?

Lux is a unit of measurement within the International System of Units that measures the perceived power of light (luminous flux) per unit area. We use Lux to measure the intensity of light when seen by the human eye, as it hits or passes through a surface. Like Candela, Lux is not as widely known as some other units of measurement related to light. However, it is very important for photometry. It is even used to help rate the lowest available light needed to film with a video camera, allowing manufacturers to rate video cameras using Lux.

Lumens Vs Watts

Now that we have covered the basics of each term, it is time to see how these units of measurement actually compare to one another. Fortunately, Lumens and Watts are pretty easy to distinguish, especially when it comes to light bulbs. As described above, Lumens measure the total light emitted by a bulb while Watts measure the amount of energy the bulb consumes. This means that we can use Lumens and Watts together to determine the relationship between energy efficiency and brightness of any given bulb.

To better illustrate the relationship between Lumens and Watts, let’s look at a few common questions: 

How many Lumens is a 60-Watt bulb?

The answer to this will actually depend on the type of bulb. For example, LED bulbs are able to produce more Lumens while burning the same amount of energy (Watts) as an incandescent bulb. Therefore, a standard 60-Watt incandescent bulb produces about 800 Lumens, while a 60-Watt LED bulb can produce upwards of 5,000 Lumens.

How many Lumens is a 100-Watt bulb?

A 100-Watt incandescent bulb produces about 1,600 Lumens, while a 100-Watt LED bulb can put out about 8,400 Lumens.

How bright are 1000 Lumens in Watts?

Comparing Lumens to Watts varies based on the energy efficiency of the bulb. Therefore, 1,000 Lumens produced by an incandescent bulb consumes about 75 Watts per hour, while 1,000 Lumens from an LED bulb consumes about 12 Watts per hour.

Are 100 Lumens the same as 100 Watts?

No, 100 Lumens are not equal to 100 Watts. Lumens measure visible light while Watts measure energy consumption. Moreover, the number of Watts required to produce 100 Lumens would be far lower than 100, regardless of the type of bulb used.

Lumens Vs Candela

Comparing Lumens and Candela can get tricky, as the former measures the amount of light produced by a given source, while the latter measures the intensity of light produced by a single source in a specific direction. So, while the two are closely related, they are used to measure different aspects of light production.

In any case, let’s try to answer a few common questions to help clear up the differences between Lumens and Candela:

Is a Lumen equal to a Candela?

Yes, one Lumen is equal to one Candela per steradian (angle).

How bright is a Candela?

The Candela gets its name from the traditional wax candle, as the brightness produced by a candle is roughly equal to one Candela.

How do you calculate Lumens from Candela?

One Candela is equal to one Lumen in a specific direction. However, this is not very useful in most situations because Candela only measures the light intensity in a single direction. Therefore, one Candela is actually closer to 12.57 Lumens, when accounting for all the light produced from a single source.

What is the difference between Lumen, Candela, and Lux?

To simplify these terms as much as possible, Lumens measure the total amount of light produced by a given light source, Candela measures the visible intensity of the light source pointed in a specific direction, and Lux measures how bright an illuminated surface will appear.

Lumens Vs Lux

The easiest way to differentiate Lumens and Lux is to think about the difference between time and space. Lumens measure the amount of light produced over a given period of time, while Lux measures the amount of light produced over a given space or area. Therefore, Lumens are more concerned with the brightness of the light source, while Lux is more concerned with how that brightness looks on a surface area.

Now that the difference between Lumens and Lux is a little bit clearer, let’s answer some common questions about these two units of measurement:

Does 1 Lux equal 1 Lumen?

Yes, one Lux is equal to 1 Lumen spread over 1 square meter.

Is 5000 Lux the same as 5000 Lumens?

Yes, depending on the surface area in question. 5,000 Lux is the same as 5,000 Lumens spread over 5,000 square meters.

How many Lux is 2000 Lumens?

The number of Lux per Lumens varies based on the surface area on which the light falls. The larger the surface area, the lower the number of Lux. For example, 2,000 Lumens over a 2-meter area will be roughly 440 Lux.

How many Lumens is a 10000 Lux light?

10,000 Lux would still be equivalent to just 1 Lumen if the surface area is also 1 meter.

We hope you found this guide on Lumens vs Watts vs Candela vs Lux both fun and informative! Are you interested in learning more about light measurements? Are you ready to purchase high-quality light bulbs at affordable prices? If so, be sure to check out the products available at Bulb Center today!