How much fragrance oil to add to candle wax

A common starting amount is 1 oz of fragrance oil per pound of wax, which CandleScience calls "6% or 1oz per pound of wax" [1]. Measured exactly, 1 oz in 16 oz of wax is 6.25 percent of the wax weight and 5.9 percent of the finished candle. Your ceiling is the lower of two numbers: the maximum your wax's data sheet allows and the maximum on your oil's IFRA certificate. This page shows how to convert between ounces per pound, percent of wax and percent of candle, what named wax suppliers publish as their limits, why more oil stops helping past a point, and why any change in load needs a new burn test.

Two ways to write a fragrance load

Every fragrance load is a fraction, and the trouble online is that people quote the top of the fraction without saying what the bottom is.

• Percent of the wax weight. Oil weight divided by wax weight. This is what "ounces per pound of wax" expresses: 1 oz per lb is 1 ÷ 16, or 6.25 percent.
• Percent of the finished candle. Oil weight divided by the total of wax plus oil. The same 1 oz in 1 lb is 1 ÷ 17, or 5.9 percent.

The two numbers are close at low loads and drift apart as the load rises. At 10 percent of the wax, the oil is 9.1 percent of the candle. At 15 percent of the wax, it is 13.0 percent of the candle.

Neither method is wrong. What goes wrong is mixing them: reading a limit written one way and measuring your batch the other. CandleScience's own beginner tutorial shows how easy the slip is. It calls 1 oz of oil in 1 lb of SimplySoy "approximately a 7% fragrance load" [2], which is neither 6.25 percent of the wax nor 5.9 percent of the candle. The tutorial's quantities are fine; only the label on them is off.

Which one suppliers use

When a supplier gives an ounces-per-pound figure next to a percentage, the pair tells you the basis. CandleScience lists SimplySoy's container maximum as "10% or 1.6 oz/lb. (45 g/454 g)" and its tealight maximum as "5% or 0.8 oz/lb. (23 g/454 g)" [3]. Since 1.6 oz is 10 percent of 16 oz, those are percent of the wax. Wholesale Supplies Plus also pairs 1 oz per pound with "about a 6% fragrance load" [4], which again only works as a percent of the wax.

Many data sheets give a bare percentage. The Golden Brands GW 464 instructions published by Voyageur Soap & Candle say "Recommended maximum scent load is about 7-9%" and do not say what the percent is of [5]. When the basis is missing, ask the seller. If you cannot find out, treat the figure as percent of the finished candle when you are near the top of the range, because that reading gives you less oil and keeps you inside the limit either way.

The conversion, worked through

The arithmetic needs only the oil weight and the wax weight.

• Percent of wax = oil ÷ wax × 100
• Percent of candle = oil ÷ (wax + oil) × 100
• Ounces per pound of wax = percent of wax × 16 ÷ 100
• To turn percent of candle into percent of wax: percent of wax = percent of candle ÷ (100 − percent of candle) × 100

The table is arithmetic only. Which row you use depends on your wax, your oil and your burn test.

Example 1: a load written as percent of wax

You have 2 lb (907 g) of wax and want 8 percent of the wax weight. Oil = 907 × 0.08 = 72.6 g, or 2.56 oz. The finished batch weighs 979.6 g, and the oil is 7.4 percent of it.

Example 2: a load written as percent of candle

You want 1,000 g of finished candle at 8 percent of the candle. Oil = 1,000 × 0.08 = 80 g. Wax = 1,000 − 80 = 920 g. As a percent of the wax, 80 ÷ 920 = 8.7 percent.

The same "8 percent" gave 72.6 g of oil per 907 g of wax in the first example and 80 g per 920 g in the second. That gap is why a recipe that does not say what its percent is of cannot be repeated exactly. The weighing side of this, including the error you make by calculating on the wrong base, is on weighing wax and fragrance. The fragrance load calculator does both directions for you.

What named waxes allow

Each figure below is that supplier's figure for that product. It does not describe soy, paraffin or coconut wax in general, and another wax of the same type can hold more or less.

If your wax came without a load figure, get the manufacturer's data sheet before you go above a modest starting amount. Reading a data sheet shows where the figure usually sits.

The oil has a limit too

The wax limit is about what the wax can hold and burn. The oil has its own limits. Many suppliers print a candle usage range on each oil: CandleScience lists its Very Vanilla oil at "Candle Safe usage: 3.0% - 10.0%" [7]. And every oil sold for candles should come with an IFRA certificate stating the most of that oil a candle can contain and still conform to the IFRA Standards. IFRA expresses its limits as a concentration "in the finished consumer product" [8], so compare the certificate's figure with your percent of candle, not your percent of wax. Some oils carry no practical limit for candles: CandleScience's example certificate lists 100 for Rose Petals in the candle category [9]. Others are restricted, and you will only know by reading the certificate. IFRA certificates and fragrance limits explains how.

Use the lowest of the three: the wax's maximum, the oil's own recommended range and the IFRA figure.

Why more oil stops making a stronger candle

Wholesale Supplies Plus puts it plainly: "adding more fragrance oil does not necessarily mean it will improve the scent throw in candles" [4]. The same source warns that more fragrance, dye or other additives raises the risk of soot, smoke and a poor burn [4]. Three things happen as you push the load toward the wax's limit:

1. The wax stops holding the oil. Oil that the wax cannot hold comes out as droplets or a film on the surface, called sweating. Oil on top of the candle covers it.
2. The candle softens. CandleScience's oven test is a useful picture of this: at 13 percent its coconut apricot candles held their shape at 113°F, and at 15 percent some melted out of their jars [6]. A softer candle travels and stores less well.
3. The wick has to change. Fragrance oil burns differently from wax, so a heavier load changes how the wick feeds.

Hot throw, the scent a lit candle gives off, also depends on the oil itself, the cure, the wick and the size of the room, as well as on load. When a candle smells weak, a candle that does not smell walks through the causes in order before you reach for more oil.

A change in load is a new candle

Wick charts assume a load. CandleScience states that "All recommendations in the Candle Wick Guide are based on a 7.5% fragrance oil load and no dyes," and that heavily fragranced candles may need a larger wick than its chart shows [10]. Supplies for Candles says higher loads may need a larger wick to keep a proper flame and melt pool, and lists a load that is too high as one cause of mushrooming, the carbon ball that forms on a wick [11]. CandleScience's coconut apricot notes add that its ECO wicks are best kept to loads of 10 percent or less [6].

So treat a load change the way you would treat a new wick or a new jar. Change the load alone, keep everything else the same, and burn test again. What has to be retested when you change something lists the other changes that count.

Setting your load in practice

1. Start inside the wax's published range. CandleScience's common starting amount, 1 oz per pound (6.25 percent of the wax) [1], sits under each wax limit in the table above.
2. Check the oil's usage range and its IFRA certificate, converted to percent of candle.
3. Weigh every gram. Record the load as a percent and state what it is a percent of.
4. Make test candles at your starting load and one step higher (for example, 6.25 and 8 percent of the wax, if both sit inside your wax's limit), with the same wick, jar and cure.
5. Burn test both and choose on throw and on burn together. If the stronger load needs a different wick to burn cleanly, that is a separate test.

From the number to the pot

Once you have a load, the next questions are practical: how to weigh small amounts of oil accurately and when to add it. Start with weighing wax and fragrance, then when and how to add fragrance, which gives the addition temperatures from the same wax data sheets used here.

References

1. CandleScience Support, How much fragrance oil should I add to melted wax?, updated April 30, 2026. https://support.candlescience.com/en_us/how-much-fragrance-oil-should-i-add-to-melted-wax-B15NnQAWl
2. CandleScience, How to Make a Soy Candle, updated October 27, 2025. https://www.candlescience.com/learning/how-to-make-a-soy-candle
3. CandleScience, CandleScience SimplySoy Artisan Wax (product page with instructions and applications), undated, read October 22, 2026. https://www.candlescience.com/wax/candlescience-simplysoy-artisan-wax
4. Wholesale Supplies Plus Help Center, How much fragrance oil do I use when making candles?, updated August 17, 2026. https://help.wholesalesuppliesplus.com/en_us/how-much-fragrance-oil-do-i-use-when-making-candles-rkMqN2evfl
5. Voyageur Soap & Candle, Golden Brands GW 464 Soy Container Candle Wax (product page with manufacturer's instructions), undated, read October 22, 2026. https://www.voyageursoapandcandle.com/Golden_Brands_464_Soy_Wax_p/20264.htm
6. CandleScience, Lab Notes: CandleScience Coconut Apricot Wax, undated (images dated April 2024), read October 22, 2026. https://candlescience.com/lab-notes-candlescience-coconut-apricot-wax
7. CandleScience, Very Vanilla Fragrance Oil (product page), undated, read October 22, 2026. https://www.candlescience.com/fragrance/very-vanilla-fragrance-oil-v1/
8. IFRA, Understanding the Standards, undated (copyright 2026), read October 22, 2026. https://ifrafragrance.org/understanding-standards
9. CandleScience, How to Use the IFRA Certificate, undated, read October 22, 2026. https://www.candlescience.com/learning/how-to-use-the-ifra-certificate/
10. CandleScience, Candle Wick (category page with wick guide notes), undated, read October 22, 2026. https://www.candlescience.com/candle-wick
11. Supplies for Candles, Candle Wicks (category page with wick notes), undated, read October 22, 2026. https://suppliesforcandles.co.uk/product-category/candle-wicks