How Do Candles Actually Work?

Candles are a fantastic lighting option that's both practical and decorative. Not only are they a small heat source and provide light, but they can also be highly decorative to suit any design or aesthetic. What makes candles unique is that the fuel source itself is the package. Fewer things are as practical and pleasing as candles!

So, how do candles work? There are two main components to a candle: 

  • Wick
  • Fuel

Each needs to have certain properties and characteristics for the candle to work properly. Let's take a more in-depth look at both of these components, so you can learn how candles work. 

What is a Wick? 

The wick is the part of the candle that is actually lit on fire. No matter what material your wick is made of, it always needs to be naturally absorbent. This absorbency is key because the wick absorbs the liquid wax as it melts to move it upward while the candle burns. This upward motion is referred to as capillary action

What Role Does Fuel Play? 

Fuel is the most important part of how do candles work. The fuel for a candle is made from wax. Different types of this material can be used depending on your preference, but the main purpose provides a source of fuel to keep the candle burning. 

As the wick does its job by pulling the liquid wax upwards, the flame's heat works to vaporize the wax. It's actually the wax vapors that burn, not the solid or liquid wax. 

How Candles Burn 

As the main source of fuel for candles, the different varieties of waxes serve as hydrocarbons. This means they are mostly made up of carbon (C) and hydrogen (H) atoms. When a candle is lit, the heat from the wick melts the wax that has been absorbed by the wick. This begins the process we mentioned earlier, known as capillary action. 

Once this wax has been absorbed by the wick and drawn up towards the top of the candle, the intense heat of the flame vaporizes the liquid wax. Basically, this heat transforms the liquid wax into a hot gas. The hydrocarbons start to break down into separate molecules of carbon and hydrogen. These molecules, now vaporized and divided, are drawn up into the flame of the candle. From this step, both the carbon and hydrogen molecules react to the oxygen in the air to create carbon dioxide, water vapor, light, and heat. This reaction creates the candle as we know it. 

Once the candle has been lit and this process begins, the heat also starts to radiate back to the candle to melt more wax to keep the process going. As long as there is enough wax, wick, and oxygen, the candle will continue burning. 

What to Watch Out For 

When a candle is first lit, it takes a few minutes for this combustion process to become stable. This translates into a flame that smokes or flickers at first since the process has yet to become stable. Once everything is stable, the flame will burn much more consistently. If you find that your candle is smoking or sputtering for a while after it's lit, it can indicate that something is wrong with the combustion process. 

The most common instance of this would be if the flame becomes too tall and strong. This happens when the flame has either too little or too much fuel or air. The flame can also flare and flicker, caused by unburned carbon particles (otherwise known as soot) that have escaped the flame before they are able to fully combust. Most commonly, this occurs if the candle wick is too long and needs to be trimmed. 

Why Do Candle Flames Always Point Up? 

When a candle is burning, it creates a cycle of upward moving air around the flame. This is due to the temperatures surrounding the flame itself. The air surrounding the candle is heated when it is lit, and hot air rises. As this warmer air rises, oxygen and cooler air rush in towards the bottom of the flame to replace it. Once this cooler air is heated, it also rises up to continue the cycle. This creates the continual up-and-down of the candle flame, creating the pointed shape we are all familiar with. 


Candles are a fun, practical way to show off your design aesthetic and to add another level of decor to your home. You can choose from different wax types or wicks depending on what works best for you and what materials you prefer. 

Shop natural soy candles to add some classic, all-natural decor to your home.