Jar Fill Calculator

Work out how much wax fills a jar to a given fill line, and how many jars a batch of wax will fill.

A jar is sold by its brim volume, but you fill it to a line well below the rim, and wax weighs less than water. This calculator turns a jar diameter, a fill height and a wax type into the wax weight per jar, then tells you how many jars a batch of wax will fill and how much is left over.

At a glance

What you enter: Wax type, Jar inside diameter, Height from the base to the fill line, Wax you have or plan to prepare, Jars you want to fill, Fragrance load
What you get: Wax per jar, Wax per jar, Jars this wax will fill, Wax left over, Wax for your target, Fragrance for your target
Formula shown: Yes, every step, right below your results.
Cost and privacy: Free, no account needed, and nothing you type is stored.

See worked examples ↓ Read the FAQ ↓ Share this calculator ↓

Wax type

Jar inside diameter in

Height from the base to the fill line in

The height you fill to, not the full height of the jar.

Wax you have or plan to prepare oz

Weight, not volume. Sixteen ounces is one pound.

Jars you want to fill

Fragrance load %

Used for the fragrance figure that goes with the wax.

Reset

Results are estimates for general information only, always verify with a professional or official source before acting on them.

How to use the Jar Fill Calculator

1 Enter Wax type
2 Enter Jar inside diameter (in)
3 Enter Height from the base to the fill line (in), The height you fill to, not the full height of the jar.
4 Enter Wax you have or plan to prepare (oz), Weight, not volume. Sixteen ounces is one pound.
5 Enter Jars you want to fill
6 Enter Fragrance load (%), Used for the fragrance figure that goes with the wax.
7 Press Calculate. You get Wax per jar, Wax per jar, Jars this wax will fill, Wax left over, Wax for your target, Fragrance for your target, and every intermediate step stays visible under "How is this calculated?"
8 Change one number at a time to see what moves the result, that is usually the most useful thing a calculator can tell you.

Worked examples

Real numbers run through this calculator. Open any example to load it into the form above and change it.

Eight ounce jelly jar in soy

A 2.6 inch inside diameter filled to 2.8 inches, with five pounds of wax on hand.

You enter

Wax type: 2
Jar inside diameter: 2.60 in
Height from the base to the fill line: 2.80 in
Wax you have or plan to prepare: 80 oz
Jars you want to fill: 12
Fragrance load: 6%

You get

Wax per jar: 7.17 oz
Wax per jar: 203.17 g
Jars this wax will fill: 11
Wax left over: 1.17 oz
Wax for your target: 86.00 oz
Fragrance for your target: 5.16 oz

About 7.2 ounces per jar, so five pounds fills eleven jars with a little over three ounces spare.

Open this example in the calculator →

Four ounce tin in a soy blend

A 2.4 inch diameter filled to 1.4 inches, working backwards from twelve tins.

You enter

Wax type: 6
Jar inside diameter: 2.40 in
Height from the base to the fill line: 1.40 in
Wax you have or plan to prepare: 32 oz
Jars you want to fill: 12
Fragrance load: 6%

You get

Wax per jar: 3.09 oz
Wax per jar: 87.55 g
Jars this wax will fill: 10
Wax left over: 1.12 oz
Wax for your target: 37.06 oz
Fragrance for your target: 2.22 oz

Two pounds fills ten tins, so prepare a little more than two pounds for twelve.

Open this example in the calculator →

20 Creative Handcraft Ideas Using Materials You Already Have

The jar of screws tipped over on the kitchen table and I just sat there, watching them roll toward the edge. I had been trying to build a spice rack out of a broken bookshelf for two hours. Nothing fi...

How to Avoid Wasting Materials When Making Crafts

Most craft waste is not caused by clumsy hands. It is caused by decisions made before you pick up a tool: buying too much, cutting before measuring, or starting a project with no plan for the offcuts....

Simple Tricks for Making Handmade Items More Durable

A handmade piece that falls apart in six months is a disappointment, not an heirloom. By the end of this guide you will know how to build durability into a project from the first cut to the final coat...

Frequently asked questions

How much wax does an 8 oz jar hold?

An 8 fluid ounce jelly jar of about 2.6 inches inside diameter, filled to about 2.8 inches, takes roughly 7.2 ounces of soy wax by weight. Jar sizes are brim volumes and wax is lighter than water, so the weight is always lower than the number on the jar. Measure your own jar diameter and fill height for the figure that applies to your container.

How many candles will 10 pounds of wax make?

At about 7 ounces of wax per 8 ounce jar, ten pounds (160 ounces) fills roughly 22 jars, and a 5 pound bag fills about 11. Small differences in fill height, spillage and what stays in the pot move that by a jar or two, so allow a spare container or two. The jars per pound figure above gives the same answer for your own jar.

How far below the rim should I fill a jar?

Most container candles are filled to between an eighth and a quarter of an inch below the rim, which leaves room for the wax to shrink as it sets and for a lid. Measure from the base to that line and enter it as the fill height. Being consistent between jars matters more than the exact number, because consistency is what makes your labels, your costs and your burn tests comparable.

Why did my jars not all take the same amount of wax?

Because wax clings to the pouring vessel, the fill line is judged by eye, and the last jar of a batch rarely gets exactly the same pour as the first. Weighing the wax into each container makes a batch that has to be identical genuinely identical. Adding the allowance from the wax calculator is what stops the last jar being the short one.

Terms used here

Short, plain-language definitions of the words this calculator uses.

Cure time The resting period after a candle is poured, before it is burned or sold, during which the fragrance binds with the wax and the scent throw develops. Melt pool The pool of liquid wax that forms around the wick as a candle burns. Wick size The thickness and construction of the wick, chosen to suit the diameter of the container and the wax being used.

Embed this calculator on your own site →