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How long will your candle actually burn
Burn time is the total number of hours a candle can burn before the wax runs out, and it is one of the first questions buyers ask. A candle that promises fifty hours but dies after twenty disappoints everyone, while a candle that honestly promises twenty hours and delivers twenty-five earns trust. Burn time depends mainly on two things: how much wax the candle holds, and how fast the flame eats that wax. The flame’s appetite, called the burn rate, is measured in grams per hour, and it changes with wick size, container width, wax type, and fragrance load. A small, narrow candle may burn only three grams per hour, while a large, wide, multi-wick candle may burn nine grams per hour or more.
The arithmetic is simple: divide the wax weight in grams by the burn rate in grams per hour, and the answer is the burn time in hours. A candle with 300 grams of wax burning at 5 grams per hour lasts about 60 hours. This estimator does that division for you, and it also shows how many days the candle lasts if you burn it for three hours a day, which is a realistic daily habit. That daily figure helps buyers picture the candle’s life: 60 hours sounds abstract, but twenty evenings of light sounds real.
How to use the burn time estimator
Weigh your wax in grams before pouring, or weigh the finished candle and subtract the container weight. Choose the burn rate that matches your candle’s size: small for narrow containers with a small wick, medium for a standard jar candle, large for a wide container, and very large for multi-wick candles. The tool shows the estimated hours and the days at three hours per day. Use these numbers on your labels only after testing, because the rate you choose is an estimate. Real candles vary, and an honest label rounds down, not up. If the tool says 58 hours and your tests show 52 to 60 hours, label the candle as 50 hours and every buyer will be pleased.
How to measure your own burn rate
Your own burn rate is more useful than any general table, and it is easy to measure. Weigh a finished candle, burn it for exactly three hours in normal room conditions, let it cool, and weigh it again. The weight lost, divided by three, is your burn rate in grams per hour. Repeat this over several burns, because the first burn often differs from later ones. Once you know your rate for a given jar, wick, and wax, you can predict burn time for every candle in that line with confidence. Record the rate with the recipe, and re-measure whenever you change wick, wax, or fragrance load, because each change moves the rate.
What shortens or lengthens burn time
Drafts are the biggest enemy of burn time. A candle near a window, fan, or air vent burns unevenly, flickers, and eats wax faster, while a candle in still air burns slowly and evenly. Long burns also waste wax: after about four hours, the melt pool gets very deep, the wick can bend, and the flame grows, which burns wax faster without giving more light. Short, regular burns of two to four hours give the longest total life and the cleanest jar. Trimming the wick to about six millimetres before each burn keeps the flame small and steady, which also stretches the hours. Finally, a candle that tunnels wastes wax on the sides, so wick choice affects burn time just as much as wax weight: the wax left on the walls is hours of light thrown away.
Using burn time honestly in your candle business
Burn time is a selling point, but only when it is honest. Buyers remember a candle that outlasted its label, and they complain loudly about one that did not. Always base labels on tested candles, not on this estimator alone, and state the burn conditions, such as three-hour burns with a trimmed wick. If you sell several sizes, the estimator helps you price fairly: a candle with twice the wax but a faster burn rate does not last twice as long, so its price should reflect real hours, not just weight. Use the tool to plan your range, test to confirm, and label with the lower end of your test results. That habit builds the trust that turns one-time buyers into repeat customers.
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