Enter: eau de toilette and eau de parfum (sometimes written as EDT and EDP). These two labels are often slapped on after the fragrances’ official name and actually can help you decode a lot about the product. EDPs typically being the stronger and longer-lasting of the two, as they have a higher concentration of oil, around 25% of fragrance oil in the potions. EDTs are often known for their lighter, airier variations, with about 15% of fragrance oil. However, in some EDT and EDP variations, the perfumer will change what notes are more pronounced, and in this case, the final profile will be different. “Fragrance notes may also be amplified for a more intense facet of the original,” notes Humbert. For example, if a fragrance has a heavy musk base in its EDP, but the perfumer highlights a lighter wood note base in the EDT, the fragrances will smell differently. However, when this happens the EDP and EDT sister scents usually smell pretty close to each other, even if a few notes have been changed. As for knowing where you fall on this spectrum, a few key questions to ask yourself from Humbert: