Using percents to measure with requires a bit of math, but the bonus is you can choose to make exactly as much of something as you want. Basically you start with the final amount you want to make, and then divide that number by 100. That gives you what 1% is. Then, multiply that up to get the amounts of each ingredient. I usually choose 100g because that means 1%=1g, so the math is super easy (and 100g is a good amount of lotion to make, it’s just under half a cup). So if I needed 20% of something, that would be 20g. If I wanted to make 50g of something, 1% would be 0.5g, so 20% = 10g.
For yields: 100g is a really nice starting point for lotions, 30–50g is good for balms and body butters as you generally use less of them. I typically stick to 20g or less for batches of lip balm (that will still be approximately 4–5 tubes of lip balm).
If you want a much easier way to do these calculations, use a spreadsheet! I have an entire blog post and video on exactly this.
For soap, just use SoapCalc—it has a column that lets you enter the amounts in as percents, and then change the batch size elsewhere. It’s awesome and does all the math for you 🙂 I recommend starting with a 500g batch.
Posted in: Measurements