Understanding Cosmetic Formulation Percentages (grams vs ml) and Formula Review

Hello! I understand that calculating percentages for cosmetic formulations can be confusing, especially when converting percentages to actual amounts and choosing between ml and g units.

Based on your questions and the responses from the staff, here is a summary and further explanation:

Calculating Ingredient Amounts from Percentages

Generally, cosmetic formulations are calculated using weight (grams) as the primary unit, not volume (ml), for each ingredient. This is because different ingredients have different densities, and measuring by volume can lead to inaccurate proportions.

Therefore, if a formula specifies a percentage (% w/w - weight by weight), it means the weight of that ingredient per 100 parts of the total weight of the formula.

Example Calculation for a 50 gram (not 50 ml) Gel Formula

If you want to make a total of 50 grams (not 50 ml) of the first gel formula you mentioned:

• Vitamin B3 4% = (4 / 100) * 50 grams = 2 grams
• n-acetyl glucosamine 4% = (4 / 100) * 50 grams = 2 grams
• Alpha Arbutin 2% = (2 / 100) * 50 grams = 1 gram
• Pro Polymer 2% (or Xanthan Gum 1%)
  • If using Pro Polymer 2% = (2 / 100) * 50 grams = 1 gram
  • If using Xanthan Gum 1% = (1 / 100) * 50 grams = 0.5 grams
• Phenoxyethanol 1% = (1 / 100) * 50 grams = 0.5 grams
• Water (the remaining percentage to reach 100%)
  • If using Pro Polymer: 100% - (4+4+2+2+1)% = 100% - 13% = 87% -> (87 / 100) * 50 grams = 43.5 grams
  • If using Xanthan Gum: 100% - (4+4+2+1+1)% = 100% - 12% = 88% -> (88 / 100) * 50 grams = 44 grams

So, the calculation of ingredient amounts should use grams for all components.

Powder Ingredients (% by Weight)

For powder ingredients listed as a percentage, you should also calculate their amount in weight (grams) based on the specified percentage. These powders are then incorporated into the formula according to the steps, which often involves dissolving or dispersing them in water or a base before combining with other ingredients.

Review of the Formulas You Asked About

1. Skin Gel Formula (First Formula):

   • The percentages add up to 100% (depending on whether you choose Pro Polymer or Xanthan Gum).
   • Calculating the amounts as described above (using grams) will be correct.
   • This formula includes key ingredients for skin strengthening (Vitamin B3) and whitening (Vitamin B3, n-acetyl glucosamine, Alpha Arbutin), along with a gelling agent and preservative. It's a good basic formula.

2. Gel Formula with Beads (Second Formula):

   • The percentages add up to 100%.
   • As the staff mentioned, this formula is incomplete because:
     • It lacks a gelling agent (Thickener), making the texture too liquid. The beads will likely settle easily. The staff recommended adding a gelling agent like Pro Polymer 1%.
     • AcneBee™ (Royal Jelly Extract) is difficult to dissolve directly in water. It may require a solubilizer or emulsifier to help it disperse well in the water phase of the formula.
   • The staff recommended making a clear gel base using Pro Polymer to showcase the beads nicely.

3. Sunscreen Formula:

   • The percentages only add up to 20% + 1% + 1.5% = 22.5%, which is far from 100%. This formula is incomplete and missing many essential components.
   • Sunscreen formulas using Titanium Dioxide Nano typically require suitable dispersing agents to ensure the Titanium Dioxide is well-dispersed and doesn't settle. They also need a base (like an emulsifier) and other ingredients to create a stable cream texture and provide effective sun protection. Please provide the complete 100% formula so the staff can offer more specific recommendations.

4. Body Whitening Cream Formula:

   • The percentages add up to 100% (5+5+5+0.5+1+1+82.5 = 100%).
   • This formula contains several beneficial ingredients for the skin.
   • For body skin that is partially dry and has some acne, the staff recommended reducing Green Tea Extract to 1-3% and adding ingredients that help strengthen the skin barrier and provide moisture, such as Safe-B3 (Vitamin B3) 5%, Vitamin B5 3%, and Shea Butter 5%. This is a good adjustment to make the formula more suitable for your specific body skin concerns.

Japanese Cherry Blossom (Bath & Body Works) Fragrance

Regarding the Japanese Cherry Blossom (Bath & Body Works) fragrance, as the staff informed you, it is currently only available in the 250g size. If you are interested, you can contact customer service at care@myskinrecipes.com to request a price quote.

I hope this explanation helps clarify the percentage calculations and cosmetic formulation process. It's great that you are learning and experimenting! If you have any further questions about adjusting formulas or ingredients, feel free to ask the staff on the webboard for their review before you start mixing.