How much sunscreen do you actually need to apply?

Why the recommended amount feels like too much, and how to get all of it on anyway.

Written by Dr. Aimee Paik, MD, board-certified dermatologist and VIZE co-founder

In short

Two finger lengths, roughly a 1/4 teaspoon, for your face and neck. That's the amount sunscreen is tested at, and research shows most people apply only 25 to 50 percent of it. At a quarter of the recommended amount, regardless of whether a sunscreen is an SPF 4 or 55, the actual real-world protection falls somewhere between SPF 2 and 10. The number on the bottle only holds true if you apply the amount it was tested with.

How much sunscreen do you need for your face?

If you take one thing from this: two finger lengths, at least a 1/4 teaspoon, for your face and neck, every morning. 

Why that amount? Sunscreen is tested in the lab at 2 milligrams per square centimeter of skin, so getting the labeled SPF depends on applying enough of it. The problem is that translating that number into real life isn’t especially straightforward.

Faces vary in size, and recommendations don’t always measure the same areas. Some include the neck, ears, or chest and some don’t. That’s why you may see advice ranging anywhere from ¼ teaspoon to a full teaspoon for the face. If you’ve ever actually measured those amounts, you know that’s a big difference.

For an average face, the amount needed to approximate the testing dose works out to around 1 gram of sunscreen. This is the amount used in clinical studies that approximate 2mg/cm2, and a number very close to what Dr. Michelle Wong from Lab Muffin got in her tape experiment to find the exact measurement of her face. But “1 gram” isn’t exactly a convenient measurement when you’re standing at the bathroom mirror. Neither is “80% of a 1/4 teaspoon.”

That’s where we came up with a good shorthand for how much to apply to the face and front half of your neck. A 1/4 teaspoon, which is roughly approximated by two finger lengths. And if you tend to use even more, even better.

Apply less than that and you won’t get the protection listed on the bottle. 

It feels like too much. We have a method.

We know you're not underapplying on purpose. A 1/4 teaspoon actually measured out feels like a lot, because it is. Think of it like a good mac and cheese. You don't want patchy bits of dry noodle. You want every piece wrapped in the same amount of sauce. That's what a 1/4 teaspoon buys you on your face: even coverage everywhere. 

Then stack it. Instead of putting the full amount on at once, apply it in two to four even layers, one right after the other, until you've used the whole quarter teaspoon. No waiting in between. We call this SPF Stacking, and it's the first thing we share when someone tells us a quarter teaspoon feels like too much. It works, and people actually end up enjoying the application.

This is why the formula matters so much. You might not mind a slightly greasy or chalky sunscreen when you're only using a little of it. But if you're going to get a full 1/4 teaspoon on, you need something non-greasy, breathable and non-pilling, that sits well over your other skincare and under whatever comes next. 

When to apply it

Every. Single. Day. If sunscreen is your whole morning routine, that's great! Wash, apply, go. A hydrating sunscreen can stand in for a moisturizer, so washing your face and putting on sunscreen is a complete routine.

If you do a little more, always apply sunscreen as the last skincare step. Toner, serums, treatments all go first. Sunscreen goes last, either after your moisturizer or in place of it. Then give it a few minutes to set before applying makeup.