Fragrance Load Explained: Percent of Wax vs Percent of Total Weight

Two candle makers can both say "I use 10% fragrance" and put different amounts of oil in the same jar. They are not disagreeing about the recipe. They are using two different definitions of fragrance load. This guide explains both, shows how far apart they really are, and helps you pick one and stick with it.

Method 1: percent of wax weight

This is the method most US wax and fragrance suppliers use, and the default in our fragrance oil calculator.

Fragrance = wax weight × load

With 16 oz of wax at 10%:

• Fragrance = 16 × 0.10 = 1.6 oz
• Total batch = 16 + 1.6 = 17.6 oz

The wax weight stays fixed and the fragrance is added on top. It is simple to calculate and matches the "ounces per pound" language you see on supplier pages.

Method 2: percent of total weight

Here the fragrance makes up a share of the finished candle.

Fragrance = total weight × load Wax = total weight − fragrance

For a 16 oz finished batch at 10%:

• Fragrance = 16 × 0.10 = 1.6 oz
• Wax = 16 − 1.6 = 14.4 oz

This method is popular with makers who think in terms of finished product, for example "this jar holds 200 g, so I need 20 g of oil at 10%". It is also common in Europe and in some wax-melt recipes.

How different are the results?

Compare the two on the same amount of wax. If you start with 16 oz of wax and want "10%":

At low loads the difference is small. At higher loads it grows. That matters most when you are close to your wax's maximum: if your wax is rated for 10% of wax weight and you follow a recipe written as 10% of total weight, you are actually at about 11.1% of the wax, which is over the limit.

Converting between the two

You can switch between methods with two short formulas:

• From percent of total (T) to percent of wax (W): W = T ÷ (1 − T)
• From percent of wax (W) to percent of total (T): T = W ÷ (1 + W)

Use decimals. For example, 10% of total is 0.10 ÷ 0.90 = 0.111, or 11.1% of wax. And 10% of wax is 0.10 ÷ 1.10 = 0.091, or 9.1% of total.

Some handy equivalents:

Which method should you use?

Use the one your wax supplier uses. Their maximum fragrance load figure is only meaningful in their own terms. If the data sheet says "up to 10%" and the supplier describes it as ounces of oil per pound of wax, they mean percent of wax weight.

Beyond that, consistency matters more than the choice. Problems start when you mix methods: following one tutorial written in percent of total, a supplier note in percent of wax and a calculator set to whichever was the default. Pick one, write it at the top of your batch log, and convert any recipe you borrow before you use it.

How this interacts with filling containers

When you know the size of your jars rather than the wax weight, the second method can feel more natural, because you know the total that needs to go in. You can still use percent of wax: divide the total fill by (1 + load) to get the wax, then multiply the wax by the load to get the fragrance.

For a jar that holds 200 g of finished candle at 8% of wax weight:

• Wax = 200 ÷ 1.08 = 185.2 g
• Fragrance = 185.2 × 0.08 = 14.8 g

That is exactly what the calculator does in "My containers" mode, so the jar fills to the same line whichever method you choose.

Common mistakes to avoid

• Adding fragrance on top of a total. Weighing 200 g of wax for a 200 g jar and then adding 8% means 216 g of liquid and a jar that overflows or leaves leftovers.
• Assuming all recipes use the same method. If a recipe does not say, ask, or test with the lower of the two interpretations first.
• Rounding too early. With small candles, rounding the wax weight before calculating the oil can shift the load by a full percentage point. Round at the end.

Frequently asked questions

Which method do candle suppliers use?

Most US suppliers express fragrance load as a percentage of wax weight, which is why you see "1 oz per pound" so often. Some European suppliers and wax-melt recipes use percent of total weight. Check the product's technical data sheet.

Does the method change how strong my candle smells?

Only because it changes the amount of oil. At the same number, percent of total puts slightly more oil in the same amount of wax.

Is one method more accurate?

Both are exact. They just answer different questions. Percent of wax tells you how much oil to add to a known amount of wax, and percent of total tells you how to split a known finished weight.