candela_watt

Candela To Watts Calculator And How To Use It?

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Have you ever wondered how to convert candela to watt? If you are interested in lighting, you might have encountered these two units of measurement. Candela is the unit of luminous intensity, which means how bright a light source is in a certain direction. Watt is the unit of power, which means how much energy a light source uses or emits.

Knowing how to convert candela to watt can help you compare different light sources and choose the best one for your needs. For example, according to the Key World Energy Statistics 2021, lighting accounted for 9% of global electricity consumption in 2018. That’s a lot of energy! By converting candela to watt, you can find out how much electricity each light source consumes and how to save money and the environment. In this guide, I will show you two ways to convert candela to watt: using a formula or using a website. I will also explain some factors that affect conversion and give you some examples and tips. Let’s get started!

Candela to Watts Calculator

Candela to Watts Conversion Table

Enter the luminous intensity in candela and either the apex angle in degrees or the solid angle in steradians. Then press the Calculate button to get the equivalent watts for incandescent, CFL, and LED lights:










Here below are some of our other calculators:

This calculator takes the luminous intensity in candelas and either the apex angle in degrees or the solid angle in steradians entered by the user. It first converts the candelas into lumens using the formula 

lumens = candela * solidAngle

 if a solid angle is provided or 

lumens = candela * (2 * Math.PI * (1 - Math.cos(radians / 2)))

 if an apex angle is provided. Then it calculates the equivalent watts for incandescent, CFL, and LED lights using the formulas:

incandescent = lumens / 14

cfl = lumens / 60

led = lumens / 90

The results are then displayed on the page, including the calculated value of lumens.

candela into watts
Candela into Watts

Using the Formula

The first way to convert candela to watt is using the formula. This calculator takes the luminous intensity in candelas and either the apex angle in degrees or the solid angle in steradians entered by the user. It first converts the candelas into lumens using the formula:

Lumens = Candela x Solid angle

if a solid angle is provided or

Lumens = Candela x (2 x Math.PI x (1 – Math.cos(radians / 2)))

if an apex angle is provided. Then it calculates the equivalent watts for incandescent, CFL, and LED lights using the formulas:

Incandescent = Lumens / 14

CFL = Lumens / 60

LED = Lumens / 90

The results are then displayed on the page, including the calculated value of lumens and watts for each type of light source.

Let me show you an example of how to use this formula. Say we have a candle that has a luminous intensity of 1 candela in all directions. We want to know how much energy it uses or gives off for different types of light sources. To do that, we need to plug in some numbers into the formula:

  • Candela = 1
  • Solid angle = 4π sr (because the candle gives off light in all directions)
  • Apex angle = not needed (if we have a solid angle)
steradian or solid angle
A for Apex Angle, π for Solid Angle

Now we can calculate the lumens and watts:

Lumens = 1 x 4π

Lumens = 12.57

Incandescent = 12.57 / 14

Incandescent = 0.90

CFL = 12.57 / 60

CFL = 0.21

LED = 12.57 / 90

LED = 0.14

So, the candle uses or gives off about 0.90 watts of energy for an incandescent light source, about 0.21 watts of energy for a CFL light source, and about 0.14 watts of energy for a LED light source.

What are the good and bad things about this method? Well, the good thing is that it is easy and practical. You don’t need to know any physics or complicated formulas. You just need to enter some numbers and get the results right away. The bad thing is that it is not very accurate or consistent. The formulas used by this calculator are based on some average values and assumptions that might not apply to all light sources or situations.

Using the Website

The second way to convert candela to watt is using our website. You don’t need to go anywhere else, because we have a free online calculator right here on this page. Just scroll up a bit, or click the link above and you will see it. All you have to do is enter the luminous intensity in candelas and either the apex angle in degrees or the solid angle in steradians. Then click on the Calculate button and you will get the luminous flux in lumens and the power consumption in watts for different types of light sources.

Let me show you an example of how to use this website. Say we have a LED bulb that has a luminous intensity of 100 candelas in one direction and a solid angle of 0.01 steradians. We want to know how much energy it uses or gives off. To do that, we just need to enter 100 into the candela box and 0.01 into the solid angle box. Then we click on the Calculate button and we get this result:

Luminous Flux (lumens): 1

Power Consumption (watts):

Incandescent: 0.07

CFL: 0.02

LED: 0.01

So, the LED bulb uses or gives off about 0.01 watts of energy for a LED light source, about 0.02 watts of energy for a CFL light source, and about 0.07 watts of energy for an incandescent light source.

What are the good and bad things about our online candle to watt calculator? Well, the good thing is that it is convenient and user-friendly. You don’t have to do any math or know any physics. You just need to enter some numbers and get the results right away. You can also compare different types of light sources and see how much energy they use or give off. The bad thing is that it is not very accurate or consistent. Our candelas into watts calculator uses some average values and assumptions that might not apply to all light sources or situations.

If you like our converter, you might also want to check out our other calculators:

  • Lumens to Candela Converter: This calculator lets you convert lumens to candela by entering the luminous flux in lumens and either the apex angle in degrees or the solid angle in steradians.
  • Candela to Lumens Converter: This calculator lets you convert candela to lumens by entering the luminous intensity in candelas and either the apex angle in degrees or the solid angle in steradians.
  • Watts to Lumens Converter: This calculator lets you convert watts to lumens by entering the power consumption in watts and the luminous efficacy in lumens per watt.
  • Lumens to Watts Converter: This calculator lets you convert lumens to watts by entering the luminous flux in lumens and the luminous efficacy in lumens per watt.

Or you can visit the “Calculators” page for more lighting related calculators.

Things that Affect the Conversion

What are the things that affect the conversion from candela to watt? Well, they are:

These things vary for different lights and situations. For example, a candle has a low luminous efficacy and a big solid angle, so it uses or gives off more energy than a LED bulb with high luminous efficacy and a small solid angle. A laser has a high luminous efficacy and a very small solid angle, so it uses or gives off very little energy compared to other lights.

Tips and Tricks for Choosing the Right Light Source Based on Candela and Watts

Now that you know how to convert candela to watt, you might wonder how to choose the right light source for your needs. There are many factors to consider when selecting a light source, such as the purpose, the location, the budget, the preference, and the environment. Here are some tips and tricks to help you make a smart and informed decision:

  • Consider the purpose of the lighting.
    What do you want to achieve with the lighting? Do you want to create a certain mood, highlight a specific object, or provide general illumination? Different purposes require different types of light sources and different levels of brightness. For example, if you want to create a cozy and romantic atmosphere, you might want to use a candle or a dimmable lamp with a low candela and watt value. If you want to showcase a painting or a sculpture, you might want to use a spotlight or a track light with a high candela and watt value. If you want to provide enough light for reading or working, you might want to use a desk lamp or a ceiling light with a moderate candela and watt value.
  • Consider the location of the lighting.
    Where do you want to place the light source? How big is the area that you want to illuminate? How far is the light source from the surface that it illuminates? Different locations require different types of light sources and different amounts of lumens. For example, if you want to light up a large room, you might want to use a chandelier or a pendant light with a high lumen value. If you want to light up a small desk, you might want to use a table lamp or a task light with a low lumen value. If you want to light up an item that is far from the light source, you might want to use a light source with a high candela value. If you want to light up an item that is close to the light source, you might want to use a light source with a low candela value.
  • Consider the budget of the lighting.
    How much money do you want to spend on the lighting? How much money do you want to save on the electricity bill? Different types of light sources have different prices and different energy efficiencies. For example, if you want to save money on the initial purchase, you might want to use an incandescent bulb or a halogen bulb with a low price but a high watt value. If you want to save money on the long-term operation, you might want to use a LED bulb or a CFL bulb with a high price but a low watt value. You can use our website or our formula to calculate how much energy each type of light source uses or gives off based on its candela and watt values.
  • Consider your preference and voice for the lighting.
    What kind of color, style, and design do you like for the lighting? What kind of message or impression do you want to convey with the lighting? Different types of light sources have different colors, styles, and designs that can affect your mood, taste, and personality. For example, if you like warm colors, you might want to use a light source with a low color temperature (below 3000K) and a long wavelength (above 600 nm), such as an incandescent bulb or an amber LED bulb. If you like cool colors, you might want to use a light source with a high color temperature (above 5000K) and a short wavelength (below 500 nm), such as a fluorescent bulb or a blue LED bulb. You can also choose from various shapes, sizes, and materials of light sources that suit your style and design preferences.
  • Consider the environment and impact of the lighting.
    How does the lighting affect your health, safety, and comfort? How does the lighting affect the environment and society? Different types of light sources have different impacts on your well-being and the world around you. For example, if you care about your health, safety, and comfort, you might want to avoid using light sources that emit harmful radiation (such as UV rays), flicker (which can cause eye strain and headaches), or glare (which can cause visual discomfort and reduced visibility). You can also adjust the brightness, color, and direction of the light source according to your needs and preferences. If you care about the environment and society, you might want to use energy-efficient, durable, and recyclable light sources that reduce greenhouse gas emissions, waste generation, and resource consumption. You can also support ethical and sustainable practices in the production, distribution, and disposal of light sources.

These are some tips and tricks for choosing the right light source based on candela and watts. Of course, there are many other factors that can influence your decision-making process. The most important thing is to find out what works best for you and your situation. Remember, there is no one-size-fits-all solution for lighting. You can always experiment, compare, and customize your lighting options until you find the perfect one for you.

candela to lumens to watt
1. Candela to Lumen, 2. Lumen to Watt

FAQ about Candela and Watt

Here are some frequently asked questions and answers about candela and watt:

Can I convert Candela into Watt?

Basically, candela and watts are not comparable units. Candela is a unit of luminous intensity, while watts is a unit of power. Luminous intensity is the measure of the amount of light emitted in a particular direction, while power is the rate at which energy is consumed.

The two units are not related, and a candela does not consume any power. Therefore, it is not possible to convert between candela and watts.

To make a candela to watts conversion, we would need to know the luminous efficacy of the light source. Luminous efficacy is the ratio of lumens to watts, and it is a measure of how efficient a light source is at converting electrical energy into light.

The luminous efficacy of different light sources varies greatly. Incandescent light bulbs have a luminous efficacy of about 15 lumens per watt, while LED light bulbs have a luminous efficacy of about 100 lumens per watt.

If we knew the luminous efficacy of the light source, we could use the following formula to convert candelas to watts:

Watts = Candelas * Luminous Efficacy

For example, if a light source has a candela rating of 1000 and a luminous efficacy of 100 lumens per watt, then it would consume 10 watts of power.

Watts = 1000 Candelas * 100 Lumens/Watt = 10 Watts

However, without knowing the luminous efficacy of the light source, it is not possible to convert a candela to watts. We have used the rule of thumb below for this calculator.

Incandescent = Lumens / 14

CFL = Lumens / 60

LED = Lumens / 90

What is the difference between candela and lumen?

Candela is the unit of luminous intensity, which means how bright a light source is in a certain direction. Lumen is the unit of luminous flux, which means how much light is emitted from a light source in all directions. One lumen is equal to one-candela times one steradian (the unit of solid angle).

How do I convert candela to lumen?

To convert candela to lumen, you need to multiply candela by the solid angle of the light source in steradians. For example, if you have a light source that has 10 candelas of luminous intensity and covers 2π steradians of solid angle, you can calculate the lumens as follows:

Lumens = Candela x Solid angle

Lumens = 10 x 2π

Lumens = 62.83

How do I convert watt to lumen?

To convert watt to lumen, you need to multiply watt by the luminous efficacy of the light source in lumens per watt. Luminous efficacy is a measure of how efficient a light source is at converting electrical power into visible light. Different types of light sources have different luminous efficacies. For example, an incandescent bulb has an average luminous efficacy of 15 lumens per watt, while a LED bulb has an average luminous efficacy of 100 lumens per watt. You can calculate the lumens as follows:

Lumens = Watt x Luminous efficacy

Lumens = 60 x 15 (for an incandescent bulb)

Lumens = 900

Lumens = 60 x 100 (for a LED bulb)

Lumens = 6000

  • Q: How many watts is a candela?
  • A: There is no fixed answer to this question, because the conversion from candela to watt depends on several factors, such as the solid angle, the luminous efficacy, and the wavelength of the light source. You can use our formula or our website to calculate the wattage of a light source based on its candela and other parameters.
  • Q: What is a candela equal to?
  • A: A candela is equal to the luminous intensity of a light source that emits one lumen of light per steradian of solid angle. A lumen is the unit of luminous flux, which measures how much light is emitted from a light source in all directions. A steradian is the unit of solid angle, which measures how much space a light source covers in 3D. One steradian is equal to the area of a cone with an angle of one radian at the tip and a radius of one unit at the base.
  • Q: How many lumens is a candela?
  • A: To convert candela to lumens, you need to multiply candela by the solid angle of the light source in steradians. For example, if you have a light source that has 10 candelas of luminous intensity and covers 2π steradians of solid angle, you can calculate the lumens as follows:

Lumens = Candela x Solid angle

Lumens = 10 x 2π

Lumens = 62.83

What is the measurement of candela light?

Candela light is measured by its luminous intensity, which is how bright a light source is in a certain direction. The unit of luminous intensity is candela (cd), which is defined as the brightness of a light source that emits one lumen of light per steradian of solid angle.

Is candela the same as watt?

No, candela and watt are not the same. Candela is the unit of luminous intensity, which measures how bright a light source is in a certain direction. Watt is the unit of power, which measures how much energy a light source uses or emits. They are related by a formula or a website that takes into account several factors, such as the solid angle, the luminous efficacy, and the wavelength of the light source.

Is a candela a unit of power?

No, a candela is not a unit of power. A candela is a unit of luminous intensity, which measures how bright a light source is in a certain direction. A unit of power is watt (W), which measures how much energy a light source uses or emits.

How much candela is a light bulb?

The amount of candela that a light bulb has depends on its type, shape, size, and distance from the surface it illuminates. Different types of light bulbs have different luminous intensities and solid angles. For example, an incandescent bulb has an average luminous intensity of 12 candelas and covers 4π steradians of solid angle, while a LED bulb has an average luminous intensity of 100 candelas and covers 0.01 steradians of solid angle.

Is candela more important than lumens?

Candela and lumens are both important units for measuring light, but they measure different aspects of it. Candela measures how bright a light source is in a certain direction, while lumens measure how much light is emitted from a light source in all directions. Depending on your purpose and preference, you might want to use either one or both of them to compare different light sources and choose the best one for your needs.

TL;DR / Conclusion


In this guide, I showed you how to convert candela to watt, which are two units of measurement for light. I explained two methods: using a formula or using a website. I also explained some factors that affect the conversion: solid angle, luminous efficacy, and wavelength. I answered some frequently asked questions and provided some tips and tricks for choosing the right light source based on candela and watt. I hope you enjoyed this guide and learned something new and useful.

As a bonus, here is a poem that I wrote about the relationship between Candela and Watt:

Candela and Watt

Candela is the brightness of a light
Watt is the power that it consumes or emits
They are related by a formula or a website
But they are also influenced by other things

Solid angle is the space that the light covers
Luminous efficacy is how efficient the light is
Wavelength is the color that the light offers
They all affect how much energy the light needs or gives

Different types of light sources have different values
For candela, watt, and the other factors
You can compare them using our calculators
And find the best one for your purposes

Candela and watt are two ways to measure light
They can help you make smart and informed choices
But they are not the only things that matter
You also need to consider your preferences and voices

Batu

Thank you for reading. If you have any questions or comments, please leave them below. I would love to hear from you. And don’t forget to share this post with your friends who might be interested in lighting. Don’t forget to check our posts about smart lighting, see you next time, and happy lighting!

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Philosophy: We want to make sure that our readers can use smart home products with maximum efficiency. Our ultimate desire in this blog is to ensure our readers use smart home gadgets to make their lives easier, more accessible, and safer.

Batu of CondoChance Team

BSc. Electrical Engineer & MBA
10+ years of industrial experience as an Electrical Engineer

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