Candle Making Calculator

Container volume	250 ml
Number of containers	4
Fragrance load	8 %

Container volume

250 ml

Number of containers

Fragrance load

8 %

Last updated: 2026-06-19

Candle Making

Planning a batch of container candles comes down to two quantities: how much wax fills the containers, and how much fragrance oil to add to that wax. Both follow directly from the container volume, the number of containers, and the fragrance load you choose.

Estimating wax from container volume

Containers are measured by volume, but wax is bought and weighed by mass, so the volume is converted using the density of solidified candle wax — roughly 0.85 grams per millilitre once melted fill and a small headspace are accounted for:

\text{wax per container} = \text{container volume (ml)} \times 0.85

\text{wax per container} = \text{container volume (fl oz)} \times 0.886

Multiplying by the number of containers gives the total wax for the batch. A common rule of thumb is that the wax in grams is about the container's millilitre volume times 0.85 — a 250 ml jar takes roughly 212 grams rather than a full 250.A common rule of thumb is that the wax in ounces is a little under the container's fluid-ounce volume — an 8 fl oz jar takes roughly 7 ounces of wax rather than a full 8.

Adding fragrance oil

Fragrance is dosed as a percentage of the total wax weight, called the fragrance load. Once the total wax is known, the oil is a simple proportion:

\begin{aligned} \text{fragrance oil} &= \text{total wax} \times \text{fragrance load} \end{aligned}

Most container waxes are rated to hold a load of 6 to 10 percent, with 8 percent a common, well-behaved starting point.

Worked example

Four 250 ml jars poured at an 8 percent fragrance load:

\begin{aligned} \text{wax per jar} &= 250 \times 0.85 = 212.5 \text{ g} \\ \text{total wax} &= 212.5 \times 4 = 850 \text{ g} \\ \text{fragrance oil} &= 850 \times 0.08 = 68 \text{ g} \end{aligned}

So the batch needs about 850 grams of wax and 68 grams of fragrance oil.

Four 8 fl oz jars poured at an 8 percent fragrance load:

\begin{aligned} \text{wax per jar} &= 8 \times 0.886 = 7.09 \text{ oz} \\ \text{total wax} &= 7.09 \times 4 = 28.4 \text{ oz} \\ \text{fragrance oil} &= 28.4 \times 0.08 = 2.27 \text{ oz} \end{aligned}

So the batch needs about 28.4 ounces (1.8 lb) of wax and 2.3 ounces of fragrance oil.

Choosing a safe fragrance load

The fragrance load is capped from two directions. First, the wax manufacturer publishes a maximum load the wax can bind; exceeding it lets oil pool, clog the wick, or pose a safety risk. Second, each fragrance oil carries an IFRA limit that sets the maximum safe concentration for that specific oil in a candle. Use whichever figure is lower, and weigh a test pour to confirm the recipe before scaling up the batch.

For scaling a recipe up or down by batch size, see the Recipe Scaler.

Frequently Asked Questions (FAQ)

Why is wax weight estimated as volume × 0.85?

A container is filled by volume but wax is sold by weight, so the volume has to be converted using the density of the wax. Melted and re-solidified candle wax has a density of roughly 0.85 grams per millilitre, lower than water, which is why a 250 ml jar takes about 212 grams of wax rather than 250. The figure also leaves a little headspace at the top of the jar. It is an estimate: soy, paraffin, and coconut waxes differ slightly, so weigh your first pour and adjust.

A container is filled by volume but wax is sold by weight, so the volume has to be converted using the density of the wax. Melted and re-solidified candle wax has a density of roughly 0.886 ounces per fluid ounce, lower than water, which is why an 8.5 fl oz jar takes about 7.5 oz of wax rather than 8.5. The figure also leaves a little headspace at the top of the jar. It is an estimate: soy, paraffin, and coconut waxes differ slightly, so weigh your first pour and adjust.

What fragrance load should I use?

Most container waxes are formulated to hold 6–10% fragrance oil by weight, and 8% is a common starting point that gives a noticeable scent without bleeding or affecting the burn.

Going above the wax manufacturer maximum can cause the oil to separate, clog the wick, or create a safety hazard. Fragrance oils also carry IFRA limits that cap how much of a given oil can be used safely in a candle, so always check both the wax rating and the specific oil documentation before increasing the load.

Does the wax type change how much I need?

Slightly. Soy wax has a density near 0.90 grams per millilitre, paraffin is around 0.90 as well when solid, and coconut and beeswax blends sit close by, but melted fill and headspace pull the practical figure down to roughly 0.85 for estimating purposes. The differences are small enough that the volume × 0.85 rule is a reliable starting estimate for any common container wax.

For a precise recipe, weigh the wax that actually fills one of your containers and scale from there.

Disclaimer

This is an estimate for planning a batch. Always follow the maximum fragrance load printed by your wax manufacturer and the IFRA limit for the specific fragrance oil, and weigh a test pour to calibrate the exact amounts for your containers and wax.

Candle Making Calculator

Inputs

Candle Making Calculator

Details

Embed this calculator

Share this calculation

Recommended Next

Recipe Scaler

Coffee-to-Water Ratio Calculator

Pizza Dough Calculator

Was this calculator helpful?

No

Candle Making Calculator

Inputs

Inputs

Results

Details

Candle Making

Estimating wax from container volume

Adding fragrance oil

Worked example

Choosing a safe fragrance load

Frequently Asked Questions (FAQ)

Disclaimer

Recommended Next

Recipe Scaler

Coffee-to-Water Ratio Calculator

Pizza Dough Calculator

Was this calculator helpful?