Deodorants and colognes are often used by people in almost the same way, without realizing the significant differences between them. In reality, even though they are both alcoholic solutions of fragrance oils, they are meant for two different purposes and should hence be used accordingly.
Deodorants are basically meant for neutralizing natural body odour. That is, it helps to reduce any bad odour that your body naturally produces throughout the day. Some brands add extra scent to deodorants but it’s not always that way.
Colognes on the other hand are meant to add extra fragrance to your body in order to smell better. It does not have any neutralizing properties.
In case of concentration, deodorants contain about 6 to 15% of fragrance oil solution in an 80% alcohol grade, while colognes or Eau De Colognes are a 3 to 6% concentration of fragrance oil solution in 70% grade of alcohol.
The lasting power of a fragrance is directly proportional to its concentration. Hence, what it implies is that the smell of cologne usually does not last that long, when compared to the fragrance contained in a deodorant. This is why you shouldn’t spray on too much deodorant in your body.