This confusion comes from the fact that some of the brands measure the size of the bottle by milliliters (ml) whereas some of the brands measure the size of the bottle by the unit fluid ounces (oz). So how you will you understand what unit is best suited for you.

To understand more of this you need to understand the equal measurement of the different measuring units. Like, for example, the meaning of 0.05 FL OZ of perfume means 1.5ml of perfume. So accordingly you can estimate. So 3.4 FL OZ perfume will be 100ml.

But the confusion might not end here; the units of US and UK are not same! In the US, the perfume bottles have their measure units written as US FL OZ. Whereas in UK, it is written as UK FL OZ.

If you are purchasing a perfume in the US which has a measuring unit of 3.4 US FL OZ then in the terms of milliliters it means 100.55ml. But in case of the same perfume in UK, which has a measuring unit of 3.4 UK FL OZ, in the terms of milliliters it means 96.60ml. So you can see that how the same measuring unit, of a 3.4 OZ perfume, in two different places has got 2 different measurements.

So from the next time whenever you go for perfume shopping, and you want a 100 ml bottle, go for a 3.4 oz perfume bottle. Also it is advisable that whenever you are going to buy a new perfume, it is way better to go for a smaller size of 30ml.

This is because all kinds of perfumes do not suit everyone. And moreover if you are going for a branded perfume then surely it will cost you a lot, so it will be a clever idea to go for the smaller bottles and trying them out first. So before you go for buying a perfume for yourself or if you are planning to gift it to someone special, be cautious about the size of the bottle.