Unit cost is not a treatment-value ranking

The dated arithmetic

The observed Mustela 40 mL cream at $17 is $42.50 per 100 mL. The selected Aveeno 532 mL lotion at $12.69 is about $2.39 per 100 mL. Aquaphor 50 g at $6.29 is $12.58 per 100 g. These are merchandise unit costs for different selected products, not a clinical ranking or a claim of interchangeable uses.

Do not rank unlike uses

Even when two offers share a volume denominator, they can differ in form, ingredients, label purpose and age wording. A larger lower-cost lotion does not automatically replace a selected face cream. The observed Aveeno label also has Drug Facts, which should remain visible rather than disappearing behind a cheapest-per 100 mL headline.

Cross-dimension refusal

The tool refuses to compare a mass denominator with a volume denominator without density. It also does not estimate an application amount, per-day cost or course of treatment. A cost per 100 g and a cost per 100 mL can both be accurately calculated while remaining unsuitable for a direct numerical winner.

Actual checkout still matters

Add actual shipping, tax and any verified promotion only when the selected order conditions are known. We did not complete checkout or verify a destination. A current product price and an old list price are not a measured savings history, and no publisher commission or approved merchant relationship is established by these observations.

Use the same complete selling unit

A $17 single tube must be divided by that tube 40 mL, not by the combined volume of several tubes shown in an image. Likewise, a confirmed multipack price needs its total declared quantity and count. Do not mix a per-unit price with a multi-unit denominator to create an artificially low cost.

Keep the formula question beside the arithmetic

A same-dimension calculation can be correct while a substitution is inappropriate. The selected cream and lotion have different form and label scope. The unit worksheet deliberately does not declare a treatment winner, estimate symptom benefit or turn a larger bottle into a recommended routine.

Before you decide

• Keep exact selected product, size and source date
• Separate label facts, source conflicts and individual questions
• Use actual package instructions; shopping tools supply no personal regimen