How Much Sunscreen to Apply: The Shot-Glass Rule
The most common sunscreen mistake isn't the brand you buy — it's how little of it you put on.
Most adults need about 1 ounce of sunscreen — roughly enough to fill a shot glass — to cover all exposed skin, plus at least 1 teaspoon for the face alone.
The American Academy of Dermatology advises applying about one ounce to cover the body and notes that most people apply only a fraction of that, which is a leading reason their protection falls short of the SPF on the label.
Questions we get a lot
How much sunscreen should I use on my body?
Most adults need about one ounce — roughly a shot glass full — to cover all exposed skin. Applying less reduces the actual SPF you receive well below the number on the label. Reapply the same amount every two hours and after swimming or heavy sweating.
How much sunscreen do I need for my face?
Plan on at least about a teaspoon of sunscreen for the face alone, and include the ears, neck, and hairline. The two-finger rule — a line of product along your index and middle fingers — is a handy shortcut. The Skin Cancer Foundation stresses that adequate quantity is essential to reaching the labeled SPF.
r/SkincareAddiction: 'Everyone says use a shot glass for your body, but how much is enough for just my face and neck?'