Eau de parfum or eau de toilette? It's not just about strength

What concentration means

Every perfume is perfume oil diluted in alcohol. The more oil, the more concentrated it is. These ranges are approximate, and each brand has its own numbers:

• Parfum / Extrait: about 20 to 30%
• Eau de parfum (EDP): about 15 to 20%
• Eau de toilette (EDT): about 5 to 15%
• Eau de Cologne (EDC): about 2 to 5%
• Eau fraîche and body mist: the lightest of all

One name, several smells

Many people think an EDP is just the EDT with less alcohol. Usually the perfumer reworks the formula for each concentration. Sauvage EDT is fresher and more peppery while the EDP is warmer, with vanilla; Bleu de Chanel comes in three versions with their own character. So if you love one version, don't blind-buy another.

Which one lasts longer?

On paper, the stronger the concentration, the longer it lasts. In practice the ingredients matter more: citrus and fresh notes fly off fast, while woods, amber, vanilla and musk stay for hours. That's why a woody EDT can outlast a citrus EDP. Rather than the label, check the longevity and projection people report on each perfume page.

Misleading names: Intense, Elixir, Absolu

These names aren't standardised and every brand uses them differently. An Intense can be an EDT or an EDP; an Elixir is usually richer and sweeter. In short: don't read too much into the version name, look at the notes and what people say.

Perfume oils and body mists

Perfume oils (like traditional attars) have no alcohol: they stay close to the skin with little projection, but often last a very long time. Body mists are the opposite: very diluted, cool and light, but gone within an hour or two.

So which should you buy?

• Hot weather, daytime and the office: usually an EDT or a lighter version.
• Evenings, parties and cold weather: an EDP or parfum.
• Don't want to fill the room: a perfume oil or a lighter version.
• Torn between two versions: one on each wrist, decide after an hour.