The name on a bottle — Cologne, Eau de Toilette, Eau de Parfum, Extrait — is not marketing fluff. It tells you the concentration of fragrance oil dissolved in alcohol. That single number shapes how strong a scent is, how long it lasts and how it evolves on skin.
The concentration ladder
Fragrance is aromatic concentrate diluted in perfumer's alcohol. The higher the concentrate load, the richer and longer-lasting the result:
- Eau de Cologne (EDC) — ~2–5% oil. Fresh, light, short-lived (2–3 h). Classic citrus splashes.
- Eau de Toilette (EDT) — ~5–15%. Bright and airy, 3–5 h. The everyday standard.
- Eau de Parfum (EDP) — ~15–20%. Rounder and stronger, 5–8 h. Today's most common format.
- Extrait / Parfum — ~20–30%. Dense, intimate, 8+ h. Less projection, more depth.
- Extrait Extrême — ~30–40%. The most concentrated tier, built for tenacity.
Does higher always mean better?
No. A bright citrus-aromatic composition can turn heavy and sour at extrait strength, while a rich amber-woody accord only reveals its full character at EDP or above. The concentration should fit the olfactory family and the balance of top, heart and base notes — which is exactly what Fragrance Analyzer flags on every formula page.
Practical takeaway
If you reformulate or dilute a concentrate yourself, start from the finished-perfume load: for 30 g of an EDP, roughly 5.4 g is concentrate and the rest is alcohol. Our unlocked formulas include a batch calculator and concentration converter that do this maths for you.