Unitised Volume Price (UVP): Simplifying the Myriad of Bottle Sizes

Once you've settled on one (or more) scents, then comes the question of which one to get based on value for money, or more often, which size of the package to choose. What makes this less than easy is the fact that there is no standardised bottle sizing used by manufacturers. There's a myriad of sizes, ranging from 20ml to 200ml and beyond, and almost everything in between.

Even more complexity arises from the different bottle sizes within houses and brands. For example, YvesSaintLaurent's female perfumes in the EDP concentration have bottle sizes of 30ml, 50ml, 90ml, whereas the male perfumes generally sell as 50ml or 100ml EDTs. Guerlain uses 30ml and 50ml for Shalimar, but L'Instant De Guerlain (EDP) has 30ml, 50ml and 80ml bottles. Almost every brand has a similar story.

So how exactly do I put them all on level footing to compare price? Simple: I unitise the volume and then price it. This gives a price figure for a single unit volume, and then I can compare prices without having to worry about different container sizes. The index that I get from this, I call it UVP (Unitised Volumetric Price). Essentially, UVP simply tells you what you are paying per unit volume for a product, regardless of brand and/or container size. 

To get the UVP, simply divide the price by the number of volume units in a bottle.

The most commonly used unit in Australia is the ml (millilitre), and that is my choice to standardise. So 100ml of perfume in a bottle that costs $200 has a UVP of $2/ml, and in my blog, I would say a UVP index of 2.

The lower the UVP for a given product, the more perfume you get for each dollar.

For Example :

Chanel's Coco Mademoiselle (and indeed most of their feminine EDPs) retails for AU$159 for 50ml, AU$234 for 100ml and AU$350 for a 200ml limited edition bottle. The 50ml bottle therefore costs $3.18/ml, the 100ml bottle costs $2.34/ml and the largest one (200ml bottle) costs $1.75/ml. The 200ml bottle offers the best value for money of the three, because you only pay $1.75 for each ml of perfume, whereas if you were to purchase a 50ml bottle, you'd pay $3.18 for each ml.

UVP is best used within a particular brand to compare value for money across different packaging sizes. However, it can also be useful for comparing and choosing across brands. If the buyer is equally satisfied with the scents and is making a decision purely on which one is better value, the one with the lower UVP should win out. 

This is the inherent limitation of UVP; it is simply a measure of how much you're paying for each unit volume of the fluid, and hence is only a quantitative metric for value for money. It does not factor in other influences, and indeed, most perfume purchases would be based on scent preference first and then value.

That said, I believe UVP is a useful tool to assist decision-making, particularly when deciding package sizes within a particular scent, or deciding between two similar scents from different houses in different package sizes. UVP immunises the measurement of value for money from both brand and package size, but is only true for the given price/size combination. Any sales/discounts should be taken into account for spontaneous comparison across brands or bottle sizes.

UVP is even more useful in skincare products, where choices can be made much more comfortably on price and value compared to fragrances.

Wait! But I use Ounces!

Most perfumes list their volume in both US fluid ounces (roughly about 30ml each, and this is the measure of conversion used by most houses) and millilitres (ml). Converting UVP from $/ml to $/oz is very simple. Just multiply the number by 30.

For example, Les Exclusifs De Chanel No. 22 sells for AU$220/75ml (UVP $2.93/ml) and AU$350/200ml (UVP $1.75/ml).

To get the UVP in $/oz, divide the price by the number of ounces. In ounces, 75ml is 2.5oz, which means at AU$220, it has a UVP of $88/oz. Similarly, the 200ml bottle , which is 6.8oz, has a UVP of $51.4/oz at its retail price of AU$350.

It does not matter whether you use US fluid ounces or millilitres; the relative proportion of the UVP values will be the same (i.e. $2.93/ml and $1.75/ml differ by the exact same proportion as $88/oz and $51.4/oz). However, make sure the units are consistent. Comparison of a dollar per ounce price with a dollar per ml price would make no sense whatsoever.

If you multiply a $/ml price by 30, it may differ slightly from the figure you would get by dividing the price with the number of ounces listed on the packaging. This is because a US ounce is not exactly 30ml (the exact value is about 29.574), and the bottles list rounded values.

The most common sizes encountered are (these are based on empirical observation of packages): 10ml (0.33 or 0.34oz), 15ml (0.5oz), 20ml (0.67 or 0.68oz), 30ml (1oz), 50ml (1.6 or 1.7oz), 75ml (2.5oz), 80ml (2.7oz), 90ml (3oz), 100ml (3.3 or 3.4oz), 125ml (4.2oz), 150ml (5oz) and 200ml (6.6, 6.7 or 6.8oz).