What is the Candle Wax Calculator?
This calculator helps candle makers estimate how much wax and fragrance oil are required to fill a batch of container candles. Instead of guessing or over-buying supplies, you enter your container volume, how many candles you plan to make, and your desired fragrance load. The tool returns the total wax weight and the matching amount of fragrance oil in both ounces and milliliters.
How to use it
Enter the container volume in fluid ounces (most votive and jar manufacturers list this), the number of containers you want to pour, and your fragrance load as a percentage (commonly 6–10% for soy and paraffin). Click calculate to see total wax, total fragrance oil, and per-container wax usage.
The formula explained
A container's volume in fluid ounces does not equal the weight of wax it holds, because wax is less dense than water and you leave headspace. The industry rule of thumb is that wax fills about 80% of the volume by weight, so: $$\text{wax\_oz} = \text{container\_vol\_oz} \times 0.8 \times \text{number\_of\_containers}$$. Fragrance oil is then dosed as a percentage of wax weight: $$\text{fragrance\_oz} = \text{wax\_oz} \times (\text{load} \div 100)$$. A higher load gives a stronger scent but most waxes max out around 10–12% before the oil bleeds out.
Worked example
Suppose you are making 6 candles in 8 fl oz jars at an 8% fragrance load. $$\text{Wax} = 8 \times 0.8 \times 6 = 38.4 \text{ oz} \ (2.4 \text{ lb})$$ $$\text{Fragrance} = 38.4 \times 0.08 = 3.072 \text{ oz}, \text{ roughly } 90.9 \text{ mL}$$ Total batch weight is about 41.47 oz.
FAQ
Why 0.8 and not 1.0? Wax weighs less than water per volume and you leave room at the top, so 80% is the standard fill-by-weight estimate.
What fragrance load should I use? 6–8% is typical; check your wax's maximum recommended load, often 10%.
Is this exact? It is a close planning estimate. Always weigh on a scale and buy a little extra wax to account for spills and testing.
