How much sunscreen to apply and how often to reapply
Natali Profumeria · 1 min read · November 1, 2026
Can you still get sunburned even when wearing sunscreen? Yes, and almost always for the same reason: you don't use enough. The SPF stated on the packaging is measured using a precise amount of product—much more generous than what we usually apply.
How much product do you need?
Tests are conducted using 2 milligrams of product for every square centimeter of skin. In everyday terms:
- Face and neck: about half a teaspoon, or two strips of product as long as your index and middle fingers.
- An adult's entire body: about six teaspoons, or approximately 30–40 grams—that is, one-fifth of a 200 ml bottle per application.
If you use half that amount, the actual protection doesn't just drop by half: it falls much further.
When to apply it
About twenty minutes before going out into the sun, apply it to dry skin, and don't forget your ears, neck, the tops of your feet, hairline, and lips (using a special stick).
How often to reapply
At least every two hours, and always after bathing, sweating heavily, or drying off with a towel, even if the sunscreen is water-resistant. Reapplying doesn't extend the protection beyond your skin's limits: it helps maintain the level of protection stated on the product.
Frequently asked questions
How much sunscreen should I put on my face?
About half a teaspoon for your face and neck, or two strips of product as long as your index and middle fingers.
How often should I reapply sunscreen?
At least every two hours, and always after bathing, sweating, or drying off with a towel, even if the product is water-resistant.
Why do I still get sunburned even when I use sunscreen?
Usually because you aren't using enough or you aren't reapplying: with half the required amount, the actual protection drops by much more than half.