Basic Terminology & Measurements: The Language of Formulation

If you're new to making your own skincare, you might find yourself wondering: What exactly is a carrier oil? Why does everyone use grams instead of teaspoons? And what do percentages have to do with it? You're not alone. Like any craft, natural skincare formulation has its own language, and once you begin to understand it, everything gets easier.

This guide will introduce you to the essential terms and measurement systems used in DIY skincare, helping you feel more confident and capable as you begin blending.

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Why Measurements Matter

When you’re first starting out, it’s tempting to scoop and pour by feel, especially if you're making a quick sugar scrub or lip balm. But if you want your formulas to be safe, consistent, and easy to recreate, precise measurement is key.

Unlike cooking, where "a pinch" or "a splash" can work just fine, skincare formulation is more like baking: it requires accuracy. Essential oils, preservatives, and active ingredients often have very specific usage rates for safety and efficacy.

That’s where grams and percentages come in.

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From Teaspoons to Grams: Why We Use Weight

Many beginner recipes are written in teaspoons or tablespoons, but professional formulators, and most experienced DIYers, use grams. Here's why:

• Precision: Grams allow for much more accurate measuring, especially for small amounts.
• Consistency: Measuring by weight ensures your formula is the same every time.
• Scalability: Working in grams and percentages makes it easy to scale up or down without doing complex math.

To get started, you’ll need a digital scale that measures to at least 0.1 grams. (We recommend one that goes to 0.01g if you plan to work with essential oils.)

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Understanding Percentages in Formulation

In skincare formulation, a recipe is often written in percentages that add up to 100%. Each ingredient is listed as a percentage of the whole. This is a universal system used by cosmetic chemists and DIY formulators alike.

Let’s say you’re making a 100g body butter:

• 70% shea butter = 70g
• 25% sweet almond oil = 25g
• 5% arrowroot powder = 5g

Total = 100g

Want to make just 50g of product instead? Divide each ingredient in half:

• 35g shea butter
• 12.5g sweet almond oil
• 2.5g arrowroot powder

Same percentages, same product, just a smaller batch.

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Key Formulation Terms to Know

Here’s a quick glossary of words you’ll see often:

• Carrier Oil: A vegetable oil used to dilute essential oils and nourish the skin (e.g., jojoba, sunflower, avocado).
• Essential Oil (EO): A concentrated plant extract that adds scent and skin benefits. Must always be diluted.
• Butter: Solid fats like shea or mango butter that add richness to formulations.
• Preservative: An ingredient that prevents microbial growth in water-based formulas. Necessary for anything that contains water or may get wet.
• Antioxidant: Protects oils from oxidizing (going rancid). Vitamin E is a common one.
• Active: A functional ingredient added to enhance the skin’s appearance or feel (e.g., niacinamide, hyaluronic acid).
• INCI Name: International Nomenclature of Cosmetic Ingredients. A standardized name for cosmetic ingredients used on labels.
• Emulsifier: Allows oil and water to mix (used in creams and lotions).
• Phase: A stage of the formulation process (typically oil phase, water phase, and cool-down phase).
• Anhydrous: A product that contains no water (e.g., balm, oil serum).

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Common Units & Conversions

• 1 gram (g) = 1000 milligrams (mg)
• 1 mL is approximately equal to 1g for water, but this changes with oils and other ingredients due to density
• Avoid volume-based units like teaspoons unless you're measuring a powder or salt
• When scaling formulations, keep all ingredient percentages the same and adjust total weight only after calculating preservative and active ingredient limits

When in doubt, weigh it out.

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A Note on Safety

Some ingredients (like essential oils or preservatives) have maximum usage rates, these are the highest percentages considered safe for skin. Always verify the recommended usage rate from your supplier or reliable cosmetic safety databases before use and do a patch test before using a new formulation.

We provide usage guidelines on all Root & Ritual base formulations and encourage customization only within safe ranges.

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Practice Tip: Start With Simple Ratios

If percentages feel overwhelming, begin with easy-to-remember ratios:

• Balm = 3 parts butter : 1 part carrier oil
• Firm Salve = 1 part carrier oil : 1 part wax : 1 part butter
• Body Oil / Face Oil = 4 parts carrier oil : 1 part accent or specialty oil
• Body Butter = 2 parts butter : 1 part carrier oil
• Sugar or Salt Scrub = 2 parts exfoliant : 1 part oil

As you gain confidence, you’ll naturally start thinking in percentages.

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Final Thoughts

Learning the language of formulation is like picking up the alphabet before writing your first poem. It gives you structure, clarity, and creative freedom.

Start small, take notes, and don’t worry if it feels awkward at first. Soon, grams and percentages will feel just as familiar as teaspoons once did, and you’ll be blending with confidence.

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Next in the Series — Understanding Shelf Life: How to Know When a Product Expires

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