The short answer
About 3.05 oz of soy wax and fragrance together (86 g), filled to 85%.
At an 8% fragrance load that's 2.82 oz of wax plus 0.23 oz of fragrance oil. Wax weighs less than water, so a jar that holds 4 fluid ounces of water holds noticeably fewer ounces of wax.
By fill level (8% fragrance)
| Fill | Total pour | Wax | Fragrance oil |
|---|---|---|---|
| 80% full | 2.87 oz 81 g | 2.66 oz 75 g | 0.21 oz 6 g |
| 85% full | 3.05 oz 86 g | 2.82 oz 80 g | 0.23 oz 6 g |
| 90% full | 3.23 oz 92 g | 2.99 oz 85 g | 0.24 oz 7 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% | 2.88 oz 82 g | 0.17 oz 5 g |
| 8% | 2.82 oz 80 g | 0.23 oz 6 g |
| 10% | 2.77 oz 79 g | 0.28 oz 8 g |
Never go above the maximum load your wax supplier lists.
Pouring a batch
| Batch | Wax to melt | Fragrance oil |
|---|---|---|
| 6 candles | 1.11 lb 504 g | 1.42 oz 40 g |
| 12 candles | 2.22 lb 1009 g | 2.85 oz 81 g |
| 24 candles | 4.45 lb 2018 g | 5.69 oz 161 g |
85% full, 8% fragrance, with 5% extra for spills and what sticks to the pot.
How this is worked out
A 4 fl oz jar holds 4.17 oz of water by weight. Filled to 85% that's 3.55 oz of water. Most container waxes weigh about 86% as much as water, which gives 3.05 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 3.41 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 4 oz of wax, pour 4 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 4 oz candle jar?
About 3.05 oz of total pour for a 4 fl oz jar filled to 85%, or 2.82 oz of wax plus 0.23 oz of fragrance oil at an 8% load.
How much fragrance oil goes in a 4 oz candle?
About 0.17 to 0.28 oz at a 6 to 10% load, filled to 85%. Check your wax's maximum load first.
Does a 4 oz jar hold 4 oz of wax?
Usually not. Jars are often sold by fluid capacity, and wax is lighter than water, so a 4 fl oz jar holds about 3.59 oz of wax when filled to the brim.
More quick answers
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