About the Candle Wax Calculator
Making container candles starts with a simple question that trips up many beginners: how much wax should I melt? Jars and tins are sold by their volume, usually in fluid ounces or millilitres, but wax is weighed. Melt too little and the last jars stay empty while you reheat; melt too much and wax is wasted. Fragrance oil adds another step, because it is measured as a percentage of the wax.
This candle wax calculator works out the wax and fragrance oil for a whole batch. Enter the jar capacity, the number of candles, how full you fill them, the fragrance load and the type of wax. It gives the wax weight in ounces, grams, pounds and kilograms, the fragrance oil weight, and the amounts for each candle.
How to Use the Candle Wax Calculator
Choose fluid ounces or millilitres for the container capacity.
Enter the capacity of one container and the number of candles.
Enter the fill level: 100% if the capacity is measured to where you want the wax to stop.
Enter the fragrance load as a percentage of the wax weight, and choose the wax.
The Formulas
fill weight (oz) = capacity (fl oz) × fill % × wax factor
wax factor: 0.86 for soy, paraffin and coconut blends; 0.96 for beeswax
wax = total fill weight ÷ (1 + fragrance load)
fragrance oil = wax × fragrance load
1 fl oz = 29.57 mL; 1 oz = 28.35 gStep-by-Step Example
Ten 8 fl oz jars of soy wax at an 8% fragrance load.
fill weight per jar = 8 × 0.86 = 6.88 oz
total fill = 6.88 × 10 = 68.8 oz
wax = 68.8 ÷ 1.08 = 63.7 oz = 3.98 lb (1.81 kg)
fragrance oil = 63.7 × 0.08 = 5.1 oz (144.5 g)Why Multiply by 0.86?
A jar's capacity is the volume of water it holds, and water weighs about 1.04 ounces per US fluid ounce. Liquid wax is lighter than water, so the same jar holds less weight of wax. Candle makers use the factor 0.86 to convert a water capacity in fluid ounces into the weight of soy or paraffin wax in ounces. Beeswax is denser, so it uses a higher factor of about 0.96. These are rules of thumb; exact values vary a little with the blend and pouring temperature.
Fragrance Load
Fragrance load is the weight of fragrance oil as a percentage of the wax weight. Most container waxes hold 6 to 10 percent, and many manufacturers list a maximum, often 10 or 12 percent. More fragrance does not always mean a stronger scent: too much can seep out of the wax, a problem called sweating, and can affect how the candle burns. One ounce of fragrance per pound of wax, a common recipe, is 6.25 percent.
The calculator keeps the total amount in each jar fixed, so adding fragrance reduces the wax slightly. That is how most makers measure: weigh the wax, then add the percentage of fragrance on top, with the combined weight filling the jar.
Melting and Pouring Tips
Melt about 10 percent more wax than the calculation shows. Some wax clings to the pouring pitcher, and many waxes, especially soy, shrink as they cool and need a small second pour to leave a smooth, flat top. Add fragrance at the temperature your wax supplier recommends, often around 85 °C (185 °F), and stir gently for a couple of minutes so it binds with the wax. Pour at the recommended temperature and let candles cure, usually for several days to two weeks, before burning for the best scent throw.
Wicks and Containers
Each candle needs a wick sized for the container's diameter and the wax type; the wick supplier's chart is the best guide. Wider jars may need two or three wicks. Use containers made for candles, which withstand heat, and leave about half an inch of space at the top.
Scaling Up Production
When making candles to sell, consistent weights matter. Weigh each jar as you pour, or pour a test candle, weigh it, and use that as the target for the batch. Record the wax lot, fragrance, load, temperatures and cure time for every batch so successful candles can be repeated exactly. The calculator's totals in pounds and kilograms help when ordering wax in bulk, which is often sold in 10 lb or 50 lb cases or in 20 kg boxes.
Measuring a Container's Capacity
If a jar's capacity is not printed, fill it with water to where you want the wax to stop, then pour the water into a measuring jug. Or weigh the jar empty and full of water: each gram of water is one millilitre. Measuring to the fill line, rather than the brim, gives the most accurate wax figure, and lets you leave the fill level at 100 percent in the calculator.
Understanding Your Result
The headline gives the total wax to melt for the batch.
The pounds and kilograms line converts the wax weight for buying in bulk.
The fragrance oil line gives the fragrance weight at your chosen load.
The per candle line gives the total fill and the wax for each container.
When Should You Use This Calculator?
Use it before each batch to weigh out wax and fragrance oil.
Use it to work out how much wax to buy for a number of candles.
Use it to compare different jar sizes and fragrance loads.
Common Mistakes
Measuring wax by volume. Weigh wax and fragrance on a scale.
Using the jar's capacity as the wax weight. Multiply by 0.86 first.
Overloading fragrance. Stay within the wax maker's maximum.
Melting exactly the calculated amount. Allow about 10% extra.