Candle Wax CalculatorFragrance Oil to Wax Ratio: How Much Oil per Batch?
Fragrance load is the most miscalculated number in candle making — most beginners take the percentage of the wax weight, which quietly under-scents every candle they pour.
This calculator uses the correct definition: fragrance load is a percentage of the finished candle (wax plus oil). Enter your wax weight and load, and it gives you the exact oil to add.
Fragrance oil to wax ratio calculator
Enter the weight of wax you are melting and your fragrance load percentage, and this calculator tells you exactly how much fragrance oil to add — and what the finished batch will weigh.
How the fragrance ratio formula works
Fragrance load is the industry-standard percentage of wax weight: fragrance_g = wax_g × (load ÷ 100), and total_batch_g = wax_g + fragrance_g.
At 8% on 500 g of wax that is 500 × 0.08 = 40 g of oil, for a 540 g finished batch. Always weigh fragrance oil on a scale — oils vary in density, so volume-measuring under- or over-doses.
Limits: the math is exact, but the safe load for your batch is set by your wax and oil suppliers’ data sheets, not by the formula.
Limits: the math is exact, but the safe load for your batch is set by your wax and your fragrance oil — always stay at or under the lower of the two rated maximums.
The correct formula, and the mistake to avoid
Fragrance load is defined as a percentage of the wax weight — the industry standard used by every major supplier. The formula is simple:
fragrance oil = wax weight × (load ÷ 100)
At 8%, that is 500 g × 0.08 = 40 g of oil, for a finished batch of 540 g. The calculator above applies exactly this formula.
A common beginner mistake is measuring the oil by volume instead of weight — fragrance oils vary in density, so always weigh the oil on a scale.
Typical fragrance loads by wax type
Safe maximums vary by wax — and by the specific fragrance oil, which may have its own lower limit. These are the usual working ranges:
| Wax | Typical load range | Common starting point |
|---|---|---|
| Soy wax | 6–10% | 8% |
| Paraffin wax | 6–10% | 8% |
| Coconut / coconut blends | 8–12% | 10% |
| Beeswax | 5–8% | 6% |
| Gel wax | 5–8% | 6% |
Soy and paraffin at 8% is the standard starting recipe for container candles. Coconut blends are known for carrying high fragrance, which is why 10% is common there. Beeswax and gel wax hold less oil cleanly, so stay conservative. Always take the lower of the wax's maximum and the fragrance oil's maximum — some oils are rated to only 6% regardless of the wax.
Worked example: a 500 g batch at 8%
Step 1 — oil: 500 g × 8% = 40 g of fragrance oil.
Step 2 — finished batch: 500 + 40 = 540 g.
Sanity check: 40 g of oil in 500 g of wax is exactly the 8% load you asked for. Weigh the oil — never measure it by volume, since fragrance oils vary in density.
Limitations
The calculator gives the mathematically correct amount for your chosen load, but it cannot tell you whether that load is safe for your wax and oil combination — the rated maximums live on your suppliers' data sheets, not in the math. Exceeding them causes sweating, poor burn, or separation.
Also, fragrance load is not the whole scent story. Throw depends on wick size, cure time, pour temperature, and the oil itself — a correctly dosed 8% candle with a bad wick will still smell weak. Treat this page as the dosing step of a longer process.
Related calculators
- Wax Melt CalculatorFree wax melt calculator: enter your clamshell cavities and segment size to get exact wax and fragrance oil amounts in grams, with a worked example.
- Soy Wax CalculatorFree soy wax calculator: enter container diameter, height, and candle count to get exact wax and fragrance oil amounts in grams, with a worked example.
- Gel Wax CalculatorFree gel wax calculator: batch gel wax weight and safe 3–5% fragrance loads.
Return to the candle wax calculator homepage to pick another tool.
Frequently asked questions
Why is the answer more than 8% of my wax weight?
Because the load percentage is defined on the finished candle — wax plus oil. An 8% load means 8% of the final weight is oil, so the oil has to be 8 ÷ 92 of the wax weight, not 8 ÷ 100. On 500 g of wax: 500 × 8 ÷ 92 = 40 g of oil, versus 40 g the wrong way.
How much fragrance oil do I add to 500 g of wax at 8%?
40 g — that is 500 × 8 ÷ 92. The finished batch weighs 540 g. If you had used the simpler 8% of wax, you would have added only 40 g and your candle would be under-scented by about 8%.
Can I use more fragrance oil than 10%?
Yes, up to the wax's rated maximum — most soy and paraffin waxes accept 10%, some coconut blends accept 12%. Going over the maximum causes sweating (oil beading on the surface), mottling, or a candle that will not stay lit properly. The percentage math has no safety limit; your wax does.
Should I measure fragrance oil in grams or millilitres?
Always by weight. Fragrance oils have densities around 0.9–1.1 g/ml, so 10 ml of oil is not 10 g — it could be anywhere from 9 to 11 g. On a 500 g batch that error compounds fast. A 0.1 g kitchen scale is the standard tool.
Does every fragrance oil work at the same load?
No — some fragrance oils have their own lower maximum, especially ones heavy in vanilla or citrus components. The safe load for a batch is the lower of the wax's maximum and the oil's maximum. If your oil is rated to 6% and your wax to 10%, use 6%.
What if I already added too little fragrance oil?
It will be under-scented, not ruined. The fix is simple: weigh out the missing oil — the difference between what you added and the correct amount — warm the batch back to pouring temperature, stir it in for two full minutes, and pour. Do not just guess and dump more in; re-weigh properly.
Found an error? Report it