Sunscreen Buying Guide

    Sunscreen Buying Guide

    Here’s the most important thing to know about sunscreen: Everyone ages 6 months and older, regardless of skin tone, should use it on exposed skin when they head outside (even on cloudy days). The second most important thing is that any sunscreen is better than none. Still, ideally you want to use a product that you can count on to fully protect your skin. CR’s ratings can help. We test sunscreens to determine their effectiveness against the sun’s ultraviolet UVA and UVB rays. We also look at how closely the sun protection factor (SPF) listed on the product’s label matches a sunscreen’s tested SPF.

    The SPF number is a measure of how well a sunscreen protects against sunburn, which is mostly the result of exposure to the sun’s UVB rays. Usually the number is explained as the amount of time it takes an individual’s exposed skin to burn when it’s covered in sunscreen compared with when it’s not. For example, if you’d normally burn after 20 minutes in the sun without sunscreen, an SPF 30 theoretically protects for 600 minutes, or 10 hours. Once the sunscreen gets on your skin, however, it begins to break down and it can also be rubbed off. So you need to reapply every 2 hours, or immediately after swimming or sweating.

    In addition, the intensity and wavelength distribution of UVB rays vary throughout the day and by location. And no sunscreen blocks 100 percent of the sun’s rays. The breakdown: SPF 30 blocks 97 percent of UVB rays, SPF 50 blocks 98 percent, and SPF 100 blocks 99 percent.

    SPF also doesn’t tell you anything about how well the sunscreen protects against UVA rays. UVA rays penetrate the skin more deeply than UVB. These are the rays that tan and age skin, and along with UVB, contribute to skin cancer. Unlike UVB rays, which are strongest from 10 a.m. to 4 p.m., UVA rays are present as long as there is daylight. That’s why you need to look for a broad-spectrum sunscreen, which protects against both UVA and UVB. Here’s what you need to know about Consumer Reports’ sunscreen testing, and how to find a product that works best for you and your family. 

    How We Test Sunscreens

    CR uses a testing protocol that is modeled on the one the Food and Drug Administration requires sunscreen manufacturers to use. But as is the case with other products we test that have government or industry standards, we use those standards as benchmarks and develop our own methodology to identify differences in performance and give consumers a comparative evaluation.

    We test only sunscreens with a listed SPF of at least 30 that are water-resistant (for 40 or 80 minutes, the two time periods for which the FDA permits water-resistance claims). We buy the sunscreens for our tests off the shelf, the way consumers would, and use three samples, preferably with different lot numbers, of each product. 

    In addition to rating each sunscreen for SPF, we test variation from SPF, and UVA protection.

    Our “variation from SPF” score gives you important information. Using a product that misses the mark could mean you’re not adequately shielding your skin. An SPF 50, say, that tests at less than half its labeled SPF in our tests would deliver an SPF 24 at the most, and sometimes far less. (The American Academy of Dermatology recommends using a product with an SPF of 30 or higher.) The meaning of our variation from SPF scores are as follows:

    Excellent: Tested 85 percent or above the labeled SPF.

    Very Good: Tested 70 percent to 84 percent of the labeled SPF.

    Good: Tested 60 percent to 69 percent of the labeled SPF.

    Fair: Tested 50 percent to 59 percent of the labeled SPF.

    Poor: Tested 49 percent or below the labeled SPF.

    Alas, there are no trips to Tahiti for our sunscreen panelists—they go to a lab. To check for SPF, a standard amount of each sunscreen is applied to a 2x3-inch rectangle on our panelists’ backs. Then they soak in a tub of water. Afterward, each of those areas is exposed to five or six intensities of ultraviolet light from a sun simulator for a set time. About a day later, the six spots are examined for redness. The resulting SPF ratings reflect each product’s effectiveness after water immersion and are based on an average of our results for each sunscreen.

    The UVA test we use allows us to differentiate the degree of UVA protection among sunscreens. To test for UVA, we smear sunscreen onto plastic plates and pass UV light through and measure the amount of UVA and UVB rays that are absorbed. That information is then used to calculate our UVA score.

    In addition, our trained sensory panel evaluates the scent and feel of every sunscreen in our tests. These sensory aspects of sunscreen are important factors to consider. You’re less likely to use a product if it smells unpleasant to you, feels sticky or greasy, or leaves white streaks on your skin. However, these factors are subjective—you may love the scent of a sunscreen, for instance, but your friend may hate it—so we don’t rate sunscreens’ scent and feel. Instead, our panel objectively evaluates and describes the scent and feel aspects so that you can choose a product that works for you. 

    Sunscreens come in a variety of fragrances. In addition to the classic beachy scent, the ones in our tests had tropical, floral, baby powder, citrus, herbal, and woodsy/outdoorsy notes. We also found that no fragrance doesn’t always mean no odor. Many fragrance-free sunscreens have a slight plastic (think beach ball) or wet-clay scent. 

    For feel, the panel considers whether the sunscreen is greasy, tacky, sticky, lightweight, or heavy. They also judge whether the product leaves a visible residue on skin, such as a shiny film or a white cast. These evaluations are performed 10 minutes after the sunscreen is applied, to give the product a chance to sink in. 

    What's in Sunscreen

    Skin cancer is the most common cancer in the U.S., and the benefits of sunscreens outweigh potential risks from their ingredients. 

    That said, there have been a lot of worrisome reports about the health effects with sunscreen chemical active ingredients—those that provide UV protection—such as oxybenzone and avobenzone. Some experts are concerned that these chemicals may be absorbed through the skin, leading to skin irritation, hormonal disruption—even skin cancer. Recently, the FDA called for more research on the safety and effectiveness of these chemicals.

    The FDA is not saying that these ingredients are unsafe. However, some chemical UV filters, such as octinoxate and oxybenzone, have been found to cause hormonal changes in animals. Short-term research in people did not show any adverse effect. And one large animal study found that the inactive ingredient retinyl palmitate, one of a group of chemical compounds related to vitamin A called retinoids, may become carcinogenic when exposed to light. But that hasn’t been studied in people. Taking pills that contain a different type of retinoid for skin conditions such as acne has been linked to birth defects. As a precaution, pregnant women may want to choose a sunscreen without the ingredient retinol palmitate or retinyl palmitate. The active ingredients are listed for each sunscreen in our ratings.

    CR’s experts say there is overwhelming evidence that sunscreen protects against skin cancer and other harmful effects of the sun, so consumers need to continue to use it on exposed skin while scientists do more research on the safety of sunscreen ingredients. 

    If you are concerned about the chemicals in sunscreen, you may wish to use a mineral (sometimes called natural) sunscreen. These contain only titanium dioxide, zinc oxide, or both as active ingredients, and there are no safety concerns about them, according to the FDA. But the downside of choosing a mineral product may be less protection. In our tests over the years, we have not found a mineral sunscreen that provides top-notch SPF and UVA protection and that has minimal variation from SPF.

    Environmental concerns also drive sunscreen choices. The majority of the sunscreens in our ratings do not contain oxybenzone or octinoxate. These two chemical active ingredients are highly effective UV filters, but they are the ones that are most often flagged as being potentially harmful to coral reefs.

    Benzene, a potential carcinogen, is another concern in spray sunscreens. This chemical isn’t an ingredient in sunscreen, but is a contaminant. How it gets into spray sunscreen isn’t known. In 2021, several sunscreens were recalled because of their benzene levels. None of the sprays in CR’s ratings were part of those recalls. (Read our article about the risks of benzene.) Sunscreen lotions are not known to contain benzene.

    Sun Protection

    You can use less sunscreen if you follow other sun protection strategies, which everyone should do anyway. Research shows that people who rely on sunscreens alone tend to burn more than those who stay in the shade and wear long sleeves. Try to avoid the sun or stay in the shade when the sun is the strongest (10 a.m. to 4 p.m.), and dress right for the occasion. Wear a hat and clothing made from tightly woven fabric. Hold clothing up to the light; if you can see through it, the UV rays can get through, too.

    When Using Sunscreen

    Check the expiration date. Sunscreen is formulated to remain effective for at least three years, according to FDA regulations. Any bottle older than that isn’t guaranteed to protect you. If the bottle or can doesn’t have an expiration date and you can’t recall when you bought it, better to play it safe and buy new sunscreen.

    Shake it. The directions might not tell you to do this, but it’s a good idea because it helps distribute the active ingredients throughout the sunscreen.

    Use enough. CR’s tests have shown that if you use half the proper amount of sunscreen, the SPF protection declines by about half. Apply sunscreen 15 to 30 minutes before you go outside. For lotions, a good rule of thumb is to use a shot glass full (about an ounce) to cover your entire bathing-suit-clad body. Or think of it as a teaspoon per body part or area: 1 teaspoon for your face, head, and neck; 1 for each arm; 1 for each leg; 1 for your chest and abdomen; and 1 for your back and the back of your neck. For sprays, apply as much as can be rubbed in, then repeat.

    Don’t forget commonly missed spots. These include the lips, backs of hands, tops of feet, back of the neck, scalp, and ears.

    Reapply. Regardless of which kind you use, reapply every 2 hours and immediately after swimming or sweating.

    Use spray sunscreens carefully. The proper way to use a spray is to hold the nozzle 4 to 6 inches away from your skin and spray until your skin glistens, then rub it in. Do this even if a spray is labeled “no rub”; smoothing it into skin increases its protection. Then repeat, just to be safe.

    The FDA has said that it is exploring the risks of inhaling spray sunscreens. Do not spray them directly on your face. Instead, spray sunscreen onto your hands, then apply it to your face. Children are more likely to inhale the mist, which could cause lung irritation. Consumer Reports recommends using a lotion on kids rather than a spray, but if you choose to use a spray, be very careful when applying it. The best thing to do is spray it into your hands and rub it onto your child’s skin. At the very least, have children close their eyes and mouth, and turn their heads while you spray. Last, sprays are flammable, so let them dry before going near an open flame.

    Bottom Line

    Check our ratings for a sunscreen that did well in our tests. If you can’t find one of those, the results of our tests over the years indicate that choosing a sunscreen with chemical active ingredients and an SPF of 40 or higher will give you a better chance of getting at least an SPF 30. Using any sunscreen is better than using none, but it’s just one part of a smart sun protection strategy.