Is the bigger bottle better value?

The calculation

Price per ml = item price ÷ volume in ml.

• A 100 ml bottle at $120 is $1.20 per ml.
• A 50 ml bottle at $85 is $1.70 per ml.

If the size is in fluid ounces, multiply by 29.57 to get ml (NIST): 3.4 fl oz is about 100 ml, 1.7 fl oz about 50 ml.

This is ordinary unit pricing, the same idea as the price per 100 ml on a supermarket shelf label. NIST's unit pricing guide recommends using one unit consistently across sizes so they can be compared, which is why we always use ml.

When it helps

• Comparing sizes of the same fragrance and concentration.
• Deciding whether a larger bottle is worth it for how often you'd wear a scent.

When it doesn't apply

• Different concentrations. EDT and EDP are different products. See EDT vs EDP vs Parfum.
• Gift sets. The price covers several items, so dividing by the main bottle's volume overstates the value. ScentsHunt doesn't show price per ml for gift sets.
• Samples, decants and minis are for trying a scent. Their per-ml price is naturally higher.

Shipping matters too

Price per ml uses the item price. A cheaper per-ml price can disappear once shipping is added, so also check the delivered total in the comparison table when the retailer provides it. More in how to compare perfume prices fairly.