The price tag on a beauty product doesn’t tell you what it actually costs per use, that depends on the product’s yield, how many layers you apply, and how often you use it. This calculator works out the real cost per application and how many days a product will last.

How to use this beauty products calculator

1. Pick a Product Type for a quick-fill efficiency estimate (mascara, eyeliner, foundation, etc.), or enter Custom.
2. Enter the product’s Efficiency (applications per mL), Volume, and Price.
3. Enter Layers per Application and Applications per Day.
4. Read how long the Product Will Last, Total Applications, and Cost per Application.

What this calculator does

Every product has an efficiency, how many single-layer applications you’d get out of each milliliter of product. This calculator multiplies that efficiency by the product’s total volume, then divides by how many layers or coats you actually use per application, to get the real total applications you’ll get out of the bottle.

Why efficiency varies so wildly by product type

A single mL of mascara yields roughly 100 single-layer applications, while the same mL of foundation yields only about 4.4, and nail polish about 3, reflecting how much product each use actually requires. This is why comparing beauty products purely on sticker price is misleading, a cheaper product with low efficiency can end up costing more per use than a pricier one that yields many more applications per mL.

Handling less-than-daily products

For products you don’t use every day, the Applications per Day field accepts a fraction, for a product used twice a week, enter 0.14 (calculated as 2 divided by 14), letting the calculator correctly stretch out the “days of use” estimate for occasional-use products rather than assuming daily application.

Frequently asked questions