Candle wax, fragrance and cost calculator
How much wax and fragrance oil to weigh for any container and batch, by either fragrance method, and what one candle really costs once breakage and testing are counted. Free, and your numbers stay in this browser.
Two methods, one word
“8% fragrance load” means two different recipes depending on who says it. Some suppliers mean 8% of the wax, added on top; others mean 8% of the finished candle. On a 200 g candle the difference is more than a gram of oil per candle, which is real money across a batch and a real difference in scent throw. This calculator asks which one you mean, and always shows what the other would have given.
Weigh a test pour, don't trust the volume
A jar's volume in millilitres is not its wax weight in grams. The usual shortcut multiplies the water weight by a factor near 0.86, but the right factor depends on your wax. The number that is never wrong is a finished test candle on the scale, minus the empty jar. Enter that once per container, and every batch after it comes out right.
The costs people leave out
- Jars that never become candles. Cracked on arrival, chipped on the bench, dropped in the sink.
- Wax and oil burned in testing. Every new scent or wick costs a few candles nobody buys.
- The label, lid and warning sticker. Small each, and on every candle.
- Your time. Melting, pouring, curing checks, labelling, packing.
The step-by-step, with the maths written out, is in how to calculate wax and fragrance for any candle container.
Questions
If I want 8% fragrance in 100 g of wax, is that 108 g or 100 g?
It depends which method you follow, and suppliers use both. Percent of wax adds the fragrance on top: 100 g wax + 8 g oil = 108 g. Total content makes the fragrance 8% of the finished candle: 92 g wax + 8 g oil = 100 g. Choose the one your wax supplier or course uses; the calculator shows what the other method would give, so the difference is never hidden.
Why not just multiply the jar volume by 0.86?
Because that factor is an average, and wax densities differ by blend and temperature. Filling to your fill line with water and multiplying is a fair first estimate, and the calculator supports it. The exact number is one real test pour: weigh the filled candle, subtract the empty jar, and use that. It is right for your wax, your jar and your fill line.
What fragrance load should I use?
Whatever your wax's data sheet gives as its maximum is the ceiling, and your fragrance supplier's usage rate may be lower still. This calculator warns above 12%, where many waxes stop holding oil, but it does not guess a number for you: the right load depends on the wax, the oil and the test burns.
Does it work for wax melts?
Yes. A wax melt is a candle without a wick: put the weight of one filled clamshell or mould cavity in as the test pour, set wicks to zero cost, and the rest is the same sum.
Why does breakage matter so much?
Because it hides in the jar price. A case of 144 jars that yields 130 candles makes every jar cost 144/130 of its invoice price, about 11% more, and that difference comes out of profit on every candle sold. The cost panel shows that hidden part separately.