Learn to formulate
A learning path, glossary, cheat sheets, troubleshooting and safety basics for making your own cosmetics.
Frequently asked questions
Do I need a preservative in every product?
Any product containing water, or likely to get wet (like a body butter in a shower), needs a broad-spectrum preservative. Truly anhydrous products such as balms and oil blends do not, but they should still contain an antioxidant.
Can I use tap water?
No. Tap water contains minerals and microbes that can destabilise your product and weaken the preservative. Use distilled or deionised water.
Can I use kitchen ingredients like honey, fruit or milk?
They are risky. Food ingredients feed microbes and are very hard to preserve reliably, so they are best kept for the kitchen.
How long will my product last?
Without stability and challenge testing, treat it as short-lived. Make small batches, keep them clean and cool, and aim to use them within a few months. Throw away anything that changes smell, colour or texture.
Why do I need a scale and not measuring spoons?
Formulas are percentages by weight. A spoonful of butter and a spoonful of glycerin weigh very different amounts, so volume measurements give unreliable results. A 0.01 g scale fixes that.
What is the difference between an INCI name and a trade name?
The INCI name is the standard ingredient name used on labels (for example Butyrospermum Parkii Butter). A trade name is a supplier's brand name for it (for example Shea Butter). Always search by INCI.
Is "natural" better or safer?
Not automatically. "Natural" is not a regulated safety term, and many natural ingredients (essential oils, some extracts) are common allergens. Judge ingredients by evidence and usage level.
How do I know how much preservative to use?
Follow the supplier's datasheet. It lists the recommended usage range, the pH range where it works and the maximum temperature to add it at.
Can essential oils preserve my product?
No. At safe levels they do not protect against microbes. Use a proper preservative.
What does Q.S. mean?
Quantum satis, "as much as needed". It marks the ingredient (usually water) that fills the formula up to 100% after everything else has been weighed.
I do not have an ingredient in a recipe. What can I do?
You can often swap in something with the same job. The Studio checks your stash against any recipe and suggests substitutions, from your own shelf or to buy, and flags what to double-check.
Can I sell what I make?
Usually only with documented safety assessments and correct labelling, and the rules differ by country. See the basics of cosmetic regulation.