Beauty Calculators
Cosmetic formula scaler.
Type your recipe as percentages and a batch size to get grams for every ingredient, with one row that takes the rest of the batch up to 100%. Or enter grams from a small test batch and get the percentages. Runs in your browser; nothing is sent or stored.
Your recipe
Grams per ingredient
Fill the form and press Calculate.
Worked example
A 200 g batch of toner: glycerin 3%, active 2%, water as the rest. Rest = 100 - 3 - 2 = 95%. Grams: glycerin 3 / 100 x 200 = 6 g, active 4 g, water 190 g, total 200 g. Reverse: 70 g water, 25 g oil, 5 g preservative in a test batch is 70%, 25% and 5%.
How it works
grams = percent / 100 x batch grams, and in the other direction percent = ingredient grams / total grams x 100. The rest-of-batch row is 100 minus the other percents. The tool warns if the percents add to more than 100, and shows the shortfall if they add to less.
Weight, not volume. Cosmetic recipes are written by weight because oils, water and powders have different densities. If you measure in ml the percentages will not hold.
This tool does not check safety. It does not know which ingredients can be combined, what preservative a water-containing product needs, or the maximum use level of any ingredient. Take those from your ingredient supplier's data sheets and the rules that apply where you sell or use the product, and keep clean equipment and records.
Sources and basis (checked 2026-10-04): pure arithmetic on the numbers you enter. For rules on what is allowed in products, see your regulator: US FDA, Cosmetics Laws and Regulations, Health Canada, Cosmetics.
FAQ
How do I scale a skincare recipe?
Write it as percent by weight, then multiply each percent by the batch size in grams and divide by 100. For a 500 g batch, 3% glycerin is 15 g.
What if my recipe is in grams already?
Switch to Grams to percent, enter the grams, and the tool gives each percent of the total. Then switch back to Percent to grams with a new batch size.
What is the rest-of-batch row?
One ingredient, usually water, set to whatever is left after the other percents. It guarantees the recipe totals 100%.
Can I use ml instead of grams?
Not reliably. A ml of oil weighs less than a ml of water or glycerin, so a recipe in volume will not match the same recipe in weight.
Does this tell me if a formula is safe or stable?
No. It only multiplies. Preservation, pH, use limits and stability are not calculated here.