DIY cosmetics

What's safe to make

Lip balms (waxes+oils), scrubs (sugar+oil), solid shampoos, hydrosol toners. Anhydrous products keep for months without preservatives.

Water-based recipes

Creams and lotions with water WITHOUT preservative — max a week in the fridge. Natural ≠ safe: essential oils — 0.5–2% dosing, citrus phototoxicity.

pH and actives

Acids (AHA/BHA, vitamin C) need pH control at 3–4 — useless without strips/meter. Niacinamide 2–5% is compatible with almost everything.

Allergy testing

Patch test on the inner elbow 24–48h before every new recipe. Top allergens: essential oils, fragrances, MIT preservatives.

Production hygiene

70% alcohol on surfaces and tools, distilled water, clean jars. A preservative dosing error = mold within a week.

Selling = regulation

Cosmetics for sale — certification, declaration of conformity, INCI labeling. 'For myself' and 'for sale' are different legal worlds.

Reference material only. Recipes are not medical advice — consult a dermatologist for skin conditions.

Sobre Cosmética casera

Cosmética casera — recetas seguras: conservantes, pH, pruebas de alergia. Química y laboratorio: Masa molar, dilución, pH, gases, seguridad. Use nuestras herramientas sin registro ni instalación de software. Todos los cálculos se realizan en su navegador — sus datos nunca se envían a un servidor.