How to work out how much wax you need for your glass

This can often be a very confusing topic when you are just starting out. Your soy wax comes in flake form but you are pouring liquid into your candle, so how do you know how much flake to melt down? A kitchen scale (the same type used for precision cooking measurements) is the easiest way to get an accurate result. Watch this short video for a simple and easy to follow calculation.

Frequently Asked Questions

How much wax do I need for my candle jar?
As a rough guide, use the jar's volume in millilitres and convert to grams using your wax's density (soy wax is roughly 0.9g/mL), then subtract a small allowance for the wick, fragrance oil volume, and headspace at the top of the jar.

Do I measure wax by weight or volume?
By weight. Wax is sold and melted by weight (grams/kg), but your jar capacity is usually listed in mL, so you need to convert between the two rather than assume they're a 1:1 match.

Why does my wax amount seem too much or too little once melted?
Solid wax flake and melted liquid wax don't take up the same space — flake is less dense, so a jar's mL capacity doesn't directly tell you how many grams of flake to melt. This is the most common confusion for beginners.

Should I fill the jar all the way to the top?
No. Leave a small gap below the rim (a few millimetres) to account for the wick tab, fragrance oil, and natural wax level changes during cooling and topping up.

Does fragrance oil change how much wax I need?
Slightly. Fragrance oil adds volume, so at higher fragrance loads you may need marginally less wax to reach the same fill level, this becomes more noticeable at 8%+ loads.