In short
Thymol is a monoterpene phenol and the main constituent of red thyme oil. It has a strong herbal, medicinal odour and is used sparingly in perfumery.
What Thymol smells like
Thymol is thyme-like, herbal and phenolic with a medicinal edge. A chemical reference describes the crystals as spicy, herbal and slightly medicinal, reminiscent of thyme; a supplier lists aromatic, thyme and leather; vendors add warm, camphoraceous and slightly sweet facets in dilution. A glossary calls it hot, almost caustic at concentration, biting and medicinal, becoming warmer and sweeter at very low dilution. It is used as a dry top note in lavender and masculine fragrances.
- Leading note
- Phenolic thyme
- Clear facets
- Medicinal
- Faint facets
- Leathery, camphoraceous
- Character
- Sharp, hot, dry
What makes Thymol distinctive
Thyme's phenol: biting and medicinal neat, warmer and sweeter in trace amounts.
Concentration and dilution
Hot, almost caustic at concentration; warmer and sweeter at very low dilution.
How Thymol is used
Used in traces as a dry top note in lavender and masculine compositions, and in oral care and flavours.
Typical role: modifier (used in small amounts to change the character of a blend).
How Thymol differs from similar materials
- Carvacrol
- Carvacrol, its isomer, is the oregano phenol; thymol is the thyme phenol. Sources disagree on which is sharper. (compared directly by a cited source)
- Thyme Oil
- Thyme oil adds camphoraceous and terpenic notes from p-cymene and gamma-terpinene to thymol. (compared directly by a cited source)
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
Phenols can irritate skin and discolour some bases. A crystalline solid; dissolve before use.
Identity and classification
- Type
- Aroma chemical
- Origin
- Occurs in nature
- Odour family
- Aromatic / Spicy
- Note position
- Heart note
- Physical form at room temperature
- Solid
- Also known as
- 2-Isopropyl-5-methylphenol
- CAS number
- 89-83-8
- Molecular formula
- C10H14O
- Molecular weight
- 150.22 g/mol
- IUPAC name
- 5-methyl-2-propan-2-ylphenol
The CAS number, formula and molecular weight are taken from PubChem compound 6989, whose own record lists this CAS number; checked 19 October 2026.
Safety and compliance
Hazard classification of the neat substance, as PubChem summarises it, read 26 October 2026. It has a harmonised EU classification (Regulation (EC) No 1272/2008, Annex VI): H302 harmful if swallowed; H314 causes severe skin burns and eye damage; H411 toxic to aquatic life with long lasting effects. Companies notifying the ECHA C&L Inventory classify it (2,007 reports): H411 toxic to aquatic life with long lasting effects (99.5% of reports); H314 causes severe skin burns and eye damage (99.4% of reports); H318 causes serious eye damage (10.5% of reports). 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
-
Carvacrol
Aroma chemical · Aromatic / Spicy — oregano, phenolic, herbal, spicy
-
Thyme Oil
Essential oil · Aromatic / Spicy — herbal, phenolic, medicinal, warm
-
p-Cymene
Aroma chemical · Citrus / Aromatic — citrus, herbal, woody, solvent-like
-
Rosemary Oil
Essential oil · Aromatic / Woody — herbal, camphoraceous, fresh, woody
Thymol is also suggested as a partner on the pages for Oregano Oil.
Used in formulas and accords
Not currently used in any published formula.
The Formula & Accord Library lists Thymol here as soon as a published formula, accord or base uses it.
Further reading
Questions about Thymol
Is Thymol natural or synthetic?
The molecule occurs in nature. Commercial Thymol 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 Thymol?
89-83-8. It was checked against PubChem on 19 October 2026.
Sources
- PubChem — compound 6989, checked 19 October 2026.
- PubChem — GHS classification (the ECHA C&L Inventory notifications and any harmonised EU entry), read 26 October 2026.
- ChemicalBook — thymol (CAS 89-83-8) — odour database.
- Symrise — Thymol crystals PH (data sheet) — manufacturer's description.
- Premiere Peau — Thymol — published perfumery reference.
- 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.