The fragrance concentration labels — Eau de Cologne, Eau de Toilette, Eau de Parfum, Extrait de Parfum — are among the most misunderstood terms in perfumery. They are routinely interpreted as a quality hierarchy, with Extrait at the top and Cologne at the bottom. This is incorrect. They describe percentage of aromatic concentrate in the finished product, and concentration affects character and behaviour, not quality.
What the labels actually mean
Each classification describes the percentage of aromatic concentrate — the blend of aroma materials — dissolved in the perfumer's alcohol that makes up the finished fragrance:
| Label | Typical concentrate % | |---|---| | Eau de Cologne (EdC) | 3–8% | | Eau de Toilette (EdT) | 8–15% | | Eau de Parfum (EdP) | 15–25% | | Extrait de Parfum | 25–40%+ |
These ranges are conventions, not legally enforced standards in most jurisdictions. A brand can label a product Eau de Parfum at 18% or 22%; the label signals approximate positioning rather than a precise figure.
The remainder of a finished fragrance is perfumer's alcohol — usually ethanol (SDA 40B or equivalent) at 95–96% purity. The alcohol is not a neutral filler: it is what allows the fragrance to spray, diffuse in air, and evaporate from skin in a controlled way. Its quality and purity affect the finished fragrance's character.
How concentration changes behaviour
This is the critical point that the quality-hierarchy interpretation misses: increasing concentration does not simply make the same fragrance stronger. It changes how the fragrance smells and behaves.
At lower concentrations, top notes have more opportunity to assert themselves. The higher alcohol content accelerates initial evaporation, brightening the opening and extending the time the fresh, volatile materials spend prominent. A bergamot-heavy Eau de Toilette opens with a more vivid citrus character than the same formula at extrait concentration, where the alcohol evaporates quickly and the concentrate's heavier character registers from the first moment.
At higher concentrations, heart and base materials assert themselves from the start. The fragrance may skip its conventional top-note impression almost entirely. An extrait of a floral fragrance can smell indistinguishable from the heart material near-neat — rich, intense, without the initial lightness that defines the fragrance as most people know it.
This means that the same formula at different concentrations is genuinely different to wear. Not better or worse — different. Many houses produce EdT and EdP versions of the same fragrance that smell distinctly unlike each other, often because the formula was adjusted (not merely diluted) for the different concentration format.
Why EdT is not inferior to EdP
An Eau de Toilette is not a compromised Eau de Parfum. It is a product designed for its concentration and formulated accordingly.
EdT concentrations suit:
- Lighter fragrance families — fresh, aquatic, green — where the character is defined by high-volatility materials that perform best at lower concentrate density
- Hot climates — higher concentrations can feel heavy and cloying in heat; EdT strengths allow a fragrance to project without overwhelming
- Daytime or professional settings — where projection needs to be contained
- Fragrances where the top note is the primary appeal — a beautiful bergamot-citrus opening that is intended to be vivid and fleeting works better at EdT than EdP
Many of the most celebrated fragrances in history were formulated as Eau de Toilette and work best at that concentration. Wearing them as EdP changes the character in ways that are sometimes an improvement and sometimes a loss of the original intent.
Extrait: intensity and trade-offs
Extrait de Parfum is widely marketed as the pinnacle of the concentration range. What you actually get is:
Higher concentrate density on skin — more material per spray, more longevity in theory.
Typically less projection than EdP — the lower alcohol content means less initial diffusion. Extrait produces a more intimate, skin-close character rather than the broader projection of an EdP at the same fragrance. If you have ever noticed that an extrait seems more personal and less room-filling than its EdP equivalent, this is the mechanism.
A potentially altered opening — heart and base materials register from the start; the fragrance may have no conventional "top note phase" at extrait strength.
The common belief that "extrait is more powerful" conflates longevity with power. In terms of sillage — the trail and projection of the fragrance — an EdP often outperforms an extrait of the same formula. Extrait performance is closer and longer; EdP performance is broader and more immediate.
Implications for building your own formulas
When you dilute a concentrate from the ScentFormulas catalogue into finished fragrance, the recommended concentration on each formula is a calibrated starting point — it reflects how the formula was developed and tested. You can and should experiment beyond that:
- 10% gives a lighter, brighter version that works in warm weather and on sensitive skin
- 20% is the standard EdP test point; this is where most formulas are designed to perform
- 30%+ gives a richer, more intense character — test whether the formula's balance still holds at this concentration before committing to a full bottle
The formula's character at each concentration is genuinely different, and one may suit your needs better than another. There is no correct concentration — only the one that gives you the result you want from that specific formula, on your skin, in your context.
Concentration is a formulation variable. Treat it like one.