How Long Will A Candle Burn Before Going Out?

A candle is a lighting device made of wax often combined with a wick that provides illumination through a flame. Candles produce light from a redox reaction, where the wax serves as the fuel and the wick serves as the catalyst. There are many factors that affect how long a candle will burn before going out, including the design of the wick, type of wax, material of the vessel, size of the candle, wick length, air currents, altitude, and any additives in the wax or wick. This article will explore these key factors that determine a candle’s burn time.

Wick Design

The type of wick used in a candle can greatly affect how long it burns. Some key factors in wick design that impact burn time include:

Wick Width – Wider wicks tend to burn faster and hotter, while narrower wicks burn slower and cooler. Wide wicks allow more wax to travel up the wick at once, feeding the flame more fuel.1

Braiding – Braided or plaited wicks burn slower and more evenly than single ply wicks. The spaces between the braids provide areas for the wax to melt into, slowing the capillary action up the wick.2

Self-Trimming – Some wicks are designed to curl back into the melted wax pool as they burn, keeping the end trimmed. This helps maintain an optimal wick length for steady, even burning.

In general, a braided wick of medium width will support a nice even burn, while a wider wick can lead to faster wax consumption and a shorter burn time.

Wax Type

The type of wax used in a candle greatly impacts its burn time. Different wax types have different melting points, which determine how quickly the wax liquefies and is consumed by the flame. The main candle wax types are:

• Paraffin – This petroleum-based wax has a low melting point of around 99°F, so it liquefies quickly and leads to a faster burn time. Paraffin candles typically burn for 5-8 hours per ounce of wax.
• Soy – Made from soybeans, this natural wax has a higher melting point between 113-127°F, resulting in slower melting and burn times of 60-80 hours for a 6 ounce candle. Soy wax is commonly used for container candles.
• Beeswax – With a melting point between 144-149°F, beeswax is very dense and slow burning. Beeswax candles can burn up to 1-2 hours per ounce, so a 14 ounce candle may burn for 14-28 hours.
• Palm – Derived from palm oil, this wax falls between paraffin and soy/beeswax in melting point. Palm wax candles tend to burn for roughly 30-40 hours per 6 ounces.
• Gel – Made from a mineral oil gel, these candles burn slowly like soy and beeswax, providing up to 80 hours of burn time per 6 ounces.

In summary, natural waxes like soy, beeswax, and palm burn slower and longer than paraffin wax. Beeswax candles have the longest burn times overall. The type of wax impacts how quickly heat is transferred to the wax pool and how fast the melted wax is consumed as fuel for the flame.

Vessel Material

The material that the candle vessel is made from can impact burn time. Common vessel materials include glass, metal, and ceramic. Glass vessels allow for complete air exposure and provide no insulation, resulting in a faster burn time. Metal vessels conduct heat away from the wax pool and can extend burn times. Ceramic vessels provide some insulation to retain heat in the wax pool, which supports a slower, longer burn.

According to research by the National Candle Association, a paraffin wax candle in a glass vessel will burn approximately one hour per ounce. The same candle in an aluminum or other metal vessel may burn up to 1.5 hours per ounce. In a ceramic vessel, burn time increases to 2-3 hours per ounce. The insulating properties of ceramic allow heat to be retained in the wax pool rather than conducted away through the vessel walls.^[1] Using a ceramic vessel can potentially double the burn time compared to an uninsulated glass vessel.

When choosing a vessel material, consider the desired burn time. Glass offers no benefit for extending burn time, while ceramic vessels can dramatically increase the hours of enjoyment per candle. Metal offers a middle ground for modestly prolonging the burn.

Candle Size

The size of a candle, specifically the diameter and height, significantly impacts how long it will burn before going out. Larger candles with more wax volume will generally burn much longer than smaller candles (source). This is because larger candles have a greater total amount of wax that must liquefy and vaporize to sustain the flame.

Taller candles also tend to burn longer than shorter candles with the same diameter, as they have more wax mass. For example, a 3-inch diameter candle that is 4 inches tall will burn for less time than a 3-inch diameter candle that is 6 inches tall (source). The taller the candle, the more total wax it contains to fuel the flame over time.

Diameter also plays an important role, as a wider candle has more surface area for the melting wax pool. This allows more wax to liquify at once and ascend the wick. A 1-inch diameter candle will generally burn for a shorter duration than a 3-inch diameter candle of equal height.

There are calculators available online that can estimate a candle’s approximate burn time based on size specifications (source). However, other factors like wax type and wick design also impact burn time.

Wick Length

The length of a candle’s wick has a significant impact on its burn time. An untrimmed wick will cause the candle to burn faster and hotter. This is because a longer wick absorbs and transports more melted wax to the flame through capillary action. More fuel results in a larger flame and faster consumption of wax.

According to research, a candle with an untrimmed wick can burn over 30% faster than one with a trimmed wick (Source). Trimming the wick to 1⁄4 inch before lighting and periodically as the candle burns helps maintain a lower and steady flame. This extends the burn time by preventing excess melted wax from being drawn up the wick.

In summary, an untrimmed wick leads to a faster burn, while a trimmed wick of about 1⁄4 inch will allow the candle to burn slower and longer. Properly trimming the wick before and during burning is key to maximizing burn time.

Air Currents

Air currents like drafts and ventilation play an important role in how quickly a candle burns. Drafts and moving air accelerate the rate at which hot air and wax vapors rise from the flame. This draws more oxygen to the flame, allowing for a hotter and faster-burning fire. That’s why candles placed near open windows, vents, fans, or air conditioning tend to burn faster than candles in still air (source).

To extend burn times, avoid drafts by placing candles away from ventilation sources. Still air allows candles to burn at their intended rate. However, completely unventilated rooms can potentially allow wax vapors and smoke to accumulate to hazardous levels. Proper ventilation should be maintained along with shielding candles from direct drafts.

Altitude

The altitude at which a candle burns has a significant impact on its burn time. At higher altitudes, there is less oxygen in the air. Oxygen helps facilitate the combustion reaction that allows a candle to burn. With less oxygen available, the flame will be smaller and the wax will melt and vaporize at a slower rate. This means that at higher elevations, candles will burn more slowly and have a longer burn time compared to burning at sea level.

For example, a candle burning in Denver, Colorado which sits at over 5,000 feet elevation may burn for 2-3 hours longer than that same candle would burn in Miami, Florida which is close to sea level. The lower oxygen concentration makes it more difficult for the wax and wick to fully combust. Tests have shown that a candle burning at 14,000 feet can have double the burn time as at sea level.

Candle manufacturers actually account for this when estimating burn times. If a candle lists a 40 hour burn time, that is usually based on burning at sea level conditions. At high altitude locations, the same candle may burn for 60-80 hours because it is utilizing oxygen less efficiently. So those living in mountainous regions will enjoy candles lasting significantly longer before going out.

Additives

Various additives can be incorporated into candle wax to modify the burning properties and appearance. According to Thompson Ferrier, additives like colorants, UV inhibitors, or hardening agents can affect how the wax melts and burns, potentially altering the burn time.¹ The Highland Candle Company notes that common additives include:

• Fragrances – Essential oils and synthetic fragrances are added for scent. Using too much fragrance can cause the candle to smoke or have an uneven melt pool.
• Dyes – Liquid or powder dyes color the wax. Darker colors tend to burn faster than lighter colors.
• Stabilizers – Additives like stearic acid and vybar harden the wax, improving burn time. Too much can make the wax brittle.

In general, the type and amount of additives can significantly impact candle burn time, scent throw, and appearance. Moderation is key to achieve optimal results.

Conclusion

In summary, there are many factors that influence how long a candle will burn before going out. The key factors include the wick design, wax type, vessel material, candle size, wick length, air currents, altitude, and any additives present. On average, a typical candle may burn anywhere from 5 hours to over 100 hours depending on these variables. Proper maintenance like trimming the wick as needed helps maximize burn time. While it’s difficult to predict an exact burn time, understanding what impacts burn time allows you to make choices that will help a candle last longer. With the right combination of design, materials, and care, it’s possible to extend a candle’s burn time significantly.