The short answer
About 9.15 oz of soy wax and fragrance together (259 g), filled to 85%.
At an 8% fragrance load that's 8.47 oz of wax plus 0.68 oz of fragrance oil. Wax weighs less than water, so a jar that holds 12 fluid ounces of water holds noticeably fewer ounces of wax.
By fill level (8% fragrance)
| Fill | Total pour | Wax | Fragrance oil |
|---|---|---|---|
| 80% full | 8.61 oz 244 g | 7.97 oz 226 g | 0.64 oz 18 g |
| 85% full | 9.15 oz 259 g | 8.47 oz 240 g | 0.68 oz 19 g |
| 90% full | 9.69 oz 275 g | 8.97 oz 254 g | 0.72 oz 20 g |
Most makers fill 80 to 90%, leaving a little headspace at the top.
By fragrance load (85% full)
| Fragrance load | Wax | Fragrance oil |
|---|---|---|
| 6% | 8.63 oz 245 g | 0.52 oz 15 g |
| 8% | 8.47 oz 240 g | 0.68 oz 19 g |
| 10% | 8.32 oz 236 g | 0.83 oz 24 g |
Never go above the maximum load your wax supplier lists.
Pouring a batch
| Batch | Wax to melt | Fragrance oil |
|---|---|---|
| 6 candles | 3.34 lb 1513 g | 4.27 oz 121 g |
| 12 candles | 6.67 lb 3027 g | 8.54 oz 242 g |
| 24 candles | 13.35 lb 6053 g | 17.08 oz 484 g |
85% full, 8% fragrance, with 5% extra for spills and what sticks to the pot.
How this is worked out
A 12 fl oz jar holds 12.52 oz of water by weight. Filled to 85% that's 10.64 oz of water. Most container waxes weigh about 86% as much as water, which gives 9.15 oz of total pour. That total is split so the fragrance oil is 8% of the wax weight.
Using beeswax? It's denser, so the same jar takes about 10.22 oz in total. Jar listed by wax weight? Some shops list how much wax a jar holds instead of its fluid capacity. If yours says it holds 12 oz of wax, pour 12 oz total. For your exact jar, weigh the water it holds to your fill line and use the water weight option in the calculator.
Common questions
How much wax do I need for a 12 oz candle jar?
About 9.15 oz of total pour for a 12 fl oz jar filled to 85%, or 8.47 oz of wax plus 0.68 oz of fragrance oil at an 8% load.
How much fragrance oil goes in a 12 oz candle?
About 0.52 to 0.83 oz at a 6 to 10% load, filled to 85%. Check your wax's maximum load first.
Does a 12 oz jar hold 12 oz of wax?
Usually not. Jars are often sold by fluid capacity, and wax is lighter than water, so a 12 fl oz jar holds about 10.77 oz of wax when filled to the brim.
More quick answers
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