Find the full-dose sunscreen amount for your exposed skin.
The exposed area in square centimeters is multiplied by the standard two milligrams per square centimeter dose. Most people apply a fraction of the tested dose, which quietly pushes real protection below the SPF number.
Sunscreen Amount
Dose = area(cm2) x 2 mg/cm2
Dose = area(cm2) x 2 mg/cm2 The exposed area in square centimeters is multiplied by the standard two milligrams per square centimeter dose.
Most people apply a fraction of the tested dose, which quietly pushes real protection below the SPF number.
This calculator takes 1 input: Exposed area. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.