How to calculate fragrance allergens for your label
Multiply each allergen's % on the supplier sheet by your fragrance load. For example, 2.5% linalool in an oil used at 3% gives 0.075% in the product. Declare it if that's above 0.01% for rinse-off products like soap, or above 0.001% for leave-on products like balm. Add up the same allergen across blended oils first.
Skip the maths: paste your sheet into the calculator.
1. Read the allergen sheet
Your fragrance supplier sends an allergen sheet (often called the EU allergen declaration or IFRA/allergen certificate) for each oil. Each line names an allergen and its % in the oil. This is the sheet for the lavender essential oil in our example balm:
Linalool 30 Linalyl acetate 35 Limonene 0.6 Camphor 0.4 Geraniol 0.3 Coumarin 0.04
If the sheet gives a range, like 20-30%, use the top value.
Only names on the EU list count. A line for a substance that isn't on it doesn't need declaring; the calculator strikes it through and keeps it aside.
2. Multiply by your fragrance load
In the product = sheet % × load % ÷ 100. Load means the oil's % of the whole batch weight. Soap recipes often give fragrance as % of the oils; convert it first (fragrance weight ÷ total batch weight × 100).
The balm uses the lavender oil at 2%:
| Allergen | On the sheet | In the product |
|---|---|---|
| Linalool | 30.00% | 0.6000% |
| Linalyl Acetate | 35.00% | 0.7000% |
| Limonene | 0.60% | 0.0120% |
| Camphor | 0.40% | 0.0080% |
| Geraniol | 0.30% | 0.0060% |
| Coumarin | 0.04% | 0.0008% |
3. Add up blended oils
When two oils carry the same allergen, add the amounts before you compare. Limonene comes from both oils in the balm:
| Oil | On the sheet | Load | In the product |
|---|---|---|---|
| Lavender essential oil | 0.60% | 2.00% | 0.0120% |
| Cedarwood atlas | 1.20% | 1.00% | 0.0120% |
| Limonene total | 0.0240% |
4. Compare with the threshold
| Product type | Declare when over |
|---|---|
| Leave-on (balm, lotion) | 0.001% |
| Rinse-off (soap, shampoo) | 0.01% |
"Over" means strictly greater. The same formula gives different labels:
- As a balm (leave-on): declare Lavandula Angustifolia Oil, Cedrus Atlantica Bark Oil, Linalyl Acetate, Linalool, Limonene, Camphor, Geraniol. Stays off: Coumarin.
- As a soap (rinse-off): declare Lavandula Angustifolia Oil, Cedrus Atlantica Bark Oil, Linalyl Acetate, Linalool, Limonene. Stays off: Camphor, Geraniol, Coumarin.
5. Write the ingredient list
List every ingredient in descending order of %, with the declared allergens in their place by their own %. An oil with no INCI name of its own is listed as "Parfum". Essential oils on the EU list (lavender, cedarwood, rose and others) are allergens themselves: name them by INCI when over the limit. The balm's label reads:
INGREDIENTS Butyrospermum Parkii Butter, Cocos Nucifera Oil, Helianthus Annuus Seed Oil, Cera Alba, Lavandula Angustifolia Oil, Cedrus Atlantica Bark Oil, Linalyl Acetate, Linalool, Limonene, Camphor, Geraniol.
The calculator does all of this as you type and shows the working for every allergen. Open it and press "See an example" to load this balm.