In short
Farnesol is a sesquiterpene alcohol occurring in linden, cyclamen and many floral oils. It brings a delicate, linden-blossom floral note.
What Farnesol smells like
Farnesol is soft, green-floral and faintly waxy, reading as linden blossom, lily of the valley and unripe pear skin, in a perfumery glossary; a review in the Journal of the Society of Cosmetic Chemists describes a delicate, sweet, oily odour developing into a floral, fresh-green note. The glossary finds it more vegetal than nerolidol, its structural isomer, which is woodier and more balsamic. It is an EU-declarable allergen.
- Leading note
- Green linden floral
- Supporting facets
- Muguet
- Faint facets
- Waxy, unripe pear skin
- Character
- Soft, fresh, mild
What makes Farnesol distinctive
Linden blossom in a molecule: soft, green and faintly waxy.
How Farnesol is used
Used in linden, muguet and soft floral compositions, and as a blender.
Typical role: fixative (slow to evaporate; helps a blend last and holds lighter notes); blender (smooths the joins between other materials).
How Farnesol differs from similar materials
- Nerolidol
- Nerolidol, its isomer, reads woodier and more balsamic; farnesol is more vegetal and linden-like. (compared directly by a cited source)
- Linden Blossom Absolute
- Linden absolute is the whole flower — honeyed, citrus-green and tea-like; farnesol is its soft green-floral note.
An asterisk marks a difference that a cited source states directly. The others compare the published descriptions of each material. Smell varies with grade, supplier and dilution; compare them side by side on blotters before substituting one for another.
Formulation considerations
A declarable allergen; IFRA lists a Standard for farnesol.
Identity and classification
- Type
- Aroma chemical
- Origin
- Occurs in nature
- Odour family
- Floral / Green
- Note position
- Base note
- Physical form at room temperature
- Liquid
- CAS number
- 4602-84-0
- Molecular formula
- C15H26O
- Molecular weight
- 222.37 g/mol
- IUPAC name
- (2E,6E)-3,7,11-trimethyldodeca-2,6,10-trien-1-ol
The CAS number, formula and molecular weight are taken from PubChem compound 445070, whose own record lists this CAS number; checked 19 October 2026.
Safety and compliance
The IFRA Standards Library lists a Standard covering Farnesol:
- "Farnesol" — type not stated in the library listing, 49th Amendment, published 2020-01
Limits differ by product category and are set out in the Standard itself; this page does not reproduce them. The list above reflects the library as read on 19 October 2026.
Farnesol is one of the 26 fragrance allergens listed individually in Annex III of the EU Cosmetics Regulation (label name: Farnesol), which must be named on cosmetic labels above 0.001% in leave-on and 0.01% in rinse-off products. Regulation (EU) 2023/1545 extended the list; see the fragrance allergens list.
Hazard classification of the neat substance, as PubChem summarises it, read 26 October 2026. Companies notifying the ECHA C&L Inventory classify it (1,980 reports): H315 causes skin irritation (99.3% of reports); H319 causes serious eye irritation (87.4% of reports); H317 may cause an allergic skin reaction (83.4% of reports); H410 very toxic to aquatic life with long lasting effects (11.1% of reports). 1 of the reports find it does not meet the hazard criteria. A skin sensitiser classification concerns handling the neat material and the dose in a finished product; the IFRA Standards, where they apply, set the limits. Unless it is harmonised, this is the notifiers' own classification, not a binding one.
This page is general information, not a safety assessment or a specification. Confirm identity, composition, IFRA status and allergen content from your supplier's documents for the lot you hold.
Materials it works with
-
Nerolidol
Aroma chemical · Floral / Woody — floral, woody, soft, faint
-
Hydroxycitronellal
Aroma chemical · Floral / Green — muguet, floral, soft, sweet
-
Linalool
Aroma chemical · Floral / Citrus — floral, fresh, woody, citrus
Farnesol is also suggested as a partner on the pages for Alpha Farnesene and Linden Blossom Absolute.
Used in formulas and accords
Used in 9 published formulas
Farnesol is an ingredient in 3 perfume formulas, 5 accords and 1 base in the Formula & Accord Library.
Community formulas
RUŌOD House Originals
Original compositions by RUŌOD House.
Further reading
Questions about Farnesol
Is Farnesol natural or synthetic?
The molecule occurs in nature. Commercial Farnesol may be made by synthesis or obtained from natural sources, so check the supplier's specification if the distinction matters to you.
What is the CAS number of Farnesol?
4602-84-0. It was checked against PubChem on 19 October 2026.
Which published formulas use Farnesol?
Farnesol is used in 9 published formulas in the RUŌOD Lab Formula & Accord Library, including Champaca Tea Room, Linden Afternoon and Mimosa Accord. Each is listed with a link under "Used in formulas and accords" on this page.
Is Farnesol covered by an IFRA Standard?
Yes. The IFRA Standards Library lists a Standard covering it: "Farnesol" — type not stated in the library listing, 49th Amendment. The limits depend on the product category; read the Standard itself before formulating.
Sources
- PubChem — compound 445070, checked 19 October 2026.
- PubChem — GHS classification (the ECHA C&L Inventory notifications and any harmonised EU entry), read 26 October 2026.
- IFRA — Standards Library, read 19 October 2026.
- EUR-Lex — Regulation (EC) No 1223/2009, Annex III.
- Premiere Peau — Farnesol — published perfumery reference.
- Journal of the Society of Cosmetic Chemists — perfumery review (farnesol) — published literature.
- Olfactory profile: the RUŌOD Lab team's synthesis of the published descriptions above, reviewed 21 October 2026. Evidence: more than one published description. Classification and the short description: revision 1. Descriptions of odour are judgement, not measurement.