How to Compare Skincare Prices Fairly
Learn to compare serum and moisturizer prices using cost per 10 ml or 100 ml, with practical examples and a buying checklist.
Why the sticker price can mislead
A €10 serum is not automatically cheaper than a €15 serum: bottle size can change the comparison. Unit pricing gives a fairer starting point for similar product types and avoids judging value by the headline price alone.
How to calculate price per 10 ml
Divide the price in euros by the number of millilitres, then multiply by 10. Formula: (price ÷ volume in ml) × 10. For example, €9 for 30 ml costs €3 per 10 ml; €12 for 60 ml costs €2 per 10 ml. Both prices are illustrative.
Example: comparing two serums
Imagine Serum A costs €7.95 for 30 ml: its unit price is €2.65 per 10 ml. Serum B costs €14 for 50 ml: its unit price is €2.80 per 10 ml. A is slightly cheaper per 10 ml, despite the lower total bottle size. Neither calculation tells you whether one formula will work better.
When price per 100 ml is better
For bigger bottles of cleanser, lotion or moisturizer, price per 100 ml may be easier to read: (price ÷ volume in ml) × 100. Compare products using the same units, and do not compare millilitres with grams as if they were identical without density information.
Check what the unit price misses
Compare products intended for similar uses and check ingredient lists, packaging, expiry guidance, retailer trust, delivery costs, refunds and how often you will use the formula. Concentrated formulas may use smaller amounts per application, so cost per use can sometimes be more relevant than cost per ml.
A simple checklist before checkout
Write down the product name, price, size, unit price, key ingredients, retailer and any missing evidence. Check whether you already own something with the same function. If available information is incomplete, delay a confident verdict rather than guessing.
Compare the product with BuyWise AI
Use BuyWise AI to review an ingredient list and price details together. Results depend on the information you provide and should be treated as shopping support rather than proof of product effectiveness. For a real example of how unit pricing informs a buying decision, read our The Ordinary niacinamide guide.
Compare at a glance
| Product example | Price / size | Cost per 10 ml |
|---|---|---|
| Serum A | €7.95 / 30 ml | €2.65 |
| Serum B | €14 / 50 ml | €2.80 |
| Serum C | €12 / 60 ml | €2.00 |
Frequently asked questions
How do I calculate price per 10 ml?
Divide the price by the volume in ml, then multiply by 10.
Is cheapest per ml always best?
No. Compare ingredients, purpose, tolerance, packaging and expected use.
Can I compare grams and ml directly?
Not without knowing the density. Use comparable units.
Read how we compare products and about BuyWise. General educational content only; not medical or dermatological advice. Consult a qualified professional for personal skin or hair concerns.