Iso E Super is a synthetic woody aroma molecule created by IFF in the 1970s. It smells dry, smooth and cedar-like with a velvety, ambery warmth, and is famous for its transparent, skin-like radiance. It is one of the most widely used ingredients in modern perfume, sometimes making up more than half of a formula.

What does Iso E Super smell like?

Iso E Super smells of polished wood seen through frosted glass: dry and cedar-like, with soft hints of vetiver, ambergris and a faint violet sweetness. It is quiet on its own and many people find it hard to smell at all, partly because the nose tires of it quickly and partly because sensitivity varies from person to person. What it does very well is add volume, smoothness and a diffusive halo around the other notes, making a fragrance feel richer and longer-lasting without adding an obvious new smell.

Where Iso E Super comes from

Iso E Super is made by chemical synthesis from inexpensive terpene-derived feedstocks and is produced in thousands of tonnes a year. It is a mixture of closely related isomers rather than a single pure compound; one minor isomer is responsible for much of its characteristic smell.

• Also known as: OTNE, tetramethyl acetyloctahydronaphthalenes
• Fragrance family: Woody ambery
• Type: Synthetic
• Made by: IFF; similar materials sold by other suppliers under different names
• How it's obtained: Chemical synthesis

Iso E Super in perfume history

John B. Hall and James M. Sanders of IFF patented it in 1973. Halston's first women's fragrance (1975) is usually cited as an early user, but the material's big moment came with Dior Fahrenheit (1988), where it was used at around a quarter of the formula. Serge Lutens' Féminité du Bois for Shiseido (1992) pushed the dose even higher, and Terre d'Hermès (2006) and Escentric Molecules Molecule 01 (2006), which contains Iso E Super alone, made it a cult ingredient.

Iso E Super in modern perfumery

Today it is everywhere, from mass-market body sprays to niche woods, and single-molecule perfumes have made it one of the few aroma chemicals known by name to the public. Perfumers use it as a smoothing agent, a woody backbone and a way to make formulas bloom on skin.

How Iso E Super wears and what it pairs with

It is a base note that lasts for many hours and often reads as the wearer's skin smelling good. It pairs with cedar, vetiver, bergamot, pepper, iris, violet, Hedione, ambroxan and musks.

Fragrances featuring Iso E Super

• Dior Fahrenheit (1988)
• Shiseido Féminité du Bois (1992)
• Hermès Terre d'Hermès (2006)
• Escentric Molecules Molecule 01 (2006)

Safety and regulation

Iso E Super is restricted by IFRA, and it was added to the EU list of labelled fragrance allergens by Regulation (EU) 2023/1545 under the name tetramethyl acetyloctahydronaphthalenes.