How to calculate the amount of wax and oils for a candle? - a practical proportion calculator

Making a candle that burns evenly and smells "like a premium one" is a bit like baking a cake: the recipe and precise proportions are key. Instead of "by eye," we switch to scales and a simple formula. In this article, I'll show you how to calculate, step by step, how much wax to pour into a mold or jar and how much oil to add to a candle to achieve exactly the scent you like. Plus, you'll get a mini proportion calculator and a cheat sheet with quick conversions. Ready? Let's get started!

Why do proportions matter?

The right proportions include a stable flame, no tunneling, clean glass walls, and a distinct but not overpowering aroma. Too little oil, and the candle will only smell in the jar. Too much, and it may smoke, crumble, set less well, or "sweat" on the surface. The right wax-to-scent ratio also affects burn time , hot throw (the intensity of the scent when burning) and cold throw (how it smells when cold).

Step 1: Determine the capacity of the vessel and the actual filling level

1. Measure the full volume of the container (in ml) using water and a measuring cup.
   

2. Plan the fill level (usually 85-90%) to leave an elegant margin from the edge.
   

3. Working volume = capacity × fill level.
   Example: 200 ml jar, 90% fill → 200 × 0.90 = 180 ml .
   

Step 2: Convert the volume to the weight of the wax

We measure the wax on a scale (in grams). For quick planning, you can use the following guidelines:

• soy wax: approx. 0.90 g/ml
  

• paraffin: approx. 0.88-0.90 g/ml
  

• coconut wax/bees-blends: usually in the range of 0.86-0.92 g/ml
  

These are approximate values ​​– different recipes have different densities. It's most likely to work if you make your own sample (measure a known volume of wax and weigh it after melting).

Pattern:
wax mass [g] = working volume [ml] × density [g/ml]

Example: 180 ml × 0.90 g/ml = 162 g of wax (approximately).

Step 3: How much fragrance oil for a candle?

In practice, we most often calculate the percentage by wax weight . The wax manufacturer also provides the maximum fragrance load (e.g., 6-10%). Always check the technical data sheet.

Pattern - variant 1 (recommended):
oil [g] = wax mass [g] × fragrance percentage

Formula - variant 2 (from total weight):
oil [g] = total weight [g] × fragrance percentage
The differences between variants are small at low percentages, but stick to one method so you can compare results.

Example starting ranges:

• soy wax + fragrance oil: 6-8%
  

• coconut/soy blend: 6-10% (depending on wax)
  

• How much essential oil should you use for a candle? For essential oils, typically 3-6% , as they are more "fickle" (affecting the flame, stability, and allergens). Always test in small samples.
  

Proportion Calculator - A Quick Recipe for Numbers

Want a ready-made solution? Here you go. Choose one method and stick with it throughout the project.

Calculator (option 1: percentage of wax mass)

1. Calculate the mass of wax:
   wax mass = working volume × density
   

2. Count the oil:
   oil = wax mass × fragrance percentage
   

3. Weight of the mixture to be poured ≈ weight of wax + oil
   

Example - 200 ml candle, 90% fill, soy wax, 7% fragrance:

• working volume: 200 ml × 0.90 = 180 ml
  

• wax weight: 180 ml × 0.90 g/ml = 162 g
  

• oil: 162 g × 0.07 = 11.34 g
  

• total to pour: approx. 173-174 g (round to convenient values)
  

Calculator (option 2: percentage of total weight)

Assume you want to pour 170g of the mixture and 7% is the fragrance:
oil = 170 × 0.07 = 11.9 g , wax ≈ 158.1 g .

Choose one variant and test - repeatability is important.

Cheat sheet: how much candle oil should you add per 100 g of wax?

This table is a quick calculator for base fragrances : you select the percentage and see how much to add per 100g of wax. For other masses, simply multiply.

How to choose the percentage for the type of fragrance?

• Light notes (tea, cucumber, ozonic, citrus) often require higher percentages within the recommended range.
  

• Heavier notes (vanilla, woody, resinous) often carry better in the air - try 6-7% .
  

• Essential oil can be more subtle in a candle than in a diffuser - start with 3-5% and test.
  

Remember: treat the wax and oil technical data sheet like a GPS - it guides you to a safe destination.

The most common mistakes when choosing proportions

1. Calculate by eye – differences of 1-2 grams can change the candle's behavior. Always use a scale.
   

2. Exceeding the maximum fragrance charge - instead of a stronger aroma, you may get smoke, a flat surface, or the candle "sweating."
   

3. Wrong moment to add the oil - add it at the wax manufacturer's recommended temperature (often 60-70°C for soy waxes), stir for 1-2 minutes to evenly disperse the molecules.
   

4. No time for "curing" (maturing) - the candle usually needs 7-14 days (vegetable waxes) for the scent to fully develop.
   

5. Mixing different calculation methods —sometimes based on wax, sometimes on total mass—makes it more difficult to compare the results and draw conclusions.
   

6. Ignoring the diameter of the vessel and the selection of the wick - even the perfect fragrance proportions will not help if the wick is too small (tunneling) or too large (smoking).
   

Mini Test Procedure (Your Repeatability in 5 Steps)

1. Weigh the empty jar and record it.
   

2. Calculate the working volume and wax mass according to density.
   

3. Select the percentage of fragrance (e.g. 6-8% for soy wax).
   

4. Melt the wax, add the oil at the appropriate temperature , mix evenly.
   

5. Pour out, cool, leave to cure , and then do a test burn (first session 2-3 hours; the melting mirror should reach almost to the edge).
   

"How much oil for soy wax?" - quick examples

• Jar 120 ml, 90% fill, soy, 6%
  working volume: 108 ml → wax weight ≈ 97 g → oil ≈ 5.8 g → total ≈ 103 g
  

• 300 ml jar, 90% fill, soy, 8%
  working volume: 270 ml → wax weight ≈ 243 g → oil ≈ 19.4 g → total ≈ 262263 g
  

Treat them as a starting point. Each wax, oil, and vessel has a slightly different "personality."

Fragrance vs. essential oils - what to watch out for?

• Fragrance oils (perfumery compositions) usually give a better hot throw at typical concentrations (6-8%).
  

• Essential oils are natural, but they tend to have more subtle scents and prefer lower percentages (3-6%) in candles. Also, check the manufacturer's flash point and IFRA recommendations.
  

• Never assume that "more is better." Sometimes a 1% difference makes all the difference.
  

What about wax mixes?

Blends (e.g., soy-coconut) often carry fragrance better and smooth the surface nicely. The calculation principle is the same, but the density and maximum fragrance charge may vary. Sample 1-2 candles at 6%, 7%, and 8% and compare cold/hot throw, appearance, and flame purity.

Summary - Your simple proportion calculator

1. Measure the capacity and assume 85-90% fill .
   

2. Convert ml → g: wax mass = ml × density (e.g. 0.90 g/ml for soy).
   

3. Select the fragrance percentage (from the wax/oil card), calculate:
   oil = wax mass × % fragrance .
   

4. Record your results, stick to one method, and test.
   

This way, you'll know how much fragrance oil to add to your candle and how much oil to add to your soy wax will work best in your jar. The rest is just pleasant practice: mixing, testing, and… delighting your family.

Got your numbers and want to quickly convert them to the next size? Use this cheat sheet (for 100g of wax) and multiply. And if you're working with a different density, swap it in the formula and you're done. Let your candle ignite a love of precision!