If you’ve ever asked yourself, “What SPF level should I use?” when choosing a sunscreen, you’re not alone. Sunscreen products can have a wide variety of SPF values—ranging from SPF 6 to 50+—that offer different levels of protection from the sun’s harmful rays. Ahead, we’re sharing some important information and tips to help you identify the right SPF value for your daily sunscreen routine.
Sun protection is an essential step in any skincare routine for healthy-looking skin, regardless of your skin tone, ethnicity, age, or lifestyle. According to the American Academy of Dermatology (AAD), applying sunscreen every day can help protect your skin from sunburn, skin cancer, and premature signs of skin aging—like fine lines, wrinkles, and dark spots—when used in conjunction with other sun protection measures.1 However, with terms such as SPF, UVA, UVB, and broad-spectrum, decoding sunscreen labels can sometimes be a bit confusing. In this guide, we’re simplifying the process of choosing a sunscreen with a full breakdown of what you should know. Keep scrolling to learn what SPF is and whether or not a higher SPF number is always better for protecting your skin.
What Is SPF?
SPF, which stands for “sun protection factor,” is a measurement of how well a sunscreen product protects your skin against UVB rays—the type of UV rays that can cause sunburns. More specifically, the SPF number tells you how long it would take for your skin to redden while wearing a specific sunscreen product versus not wearing any sunscreen at all. For example, your skin would theoretically take 50 times longer to redden with an SPF 50 sunscreen than it would without one (when measured under the same circumstances).
Sunscreens are formulated with a range of SPF values, with some of the most common being SPF 15, SPF 30, and SPF 50. According to the Journal of Clinical and Aesthetic Dermatology (JCAD), SPF values are usually broken up into four main categories: low (SPF 6 to 10), medium (SPF 15, 20, and 25), high (SPF 30 and 50), and very high (SPF 50+), although the US FDA does not recognize these distinctions.
UVA vs. UVB Protection
Since SPF only applies to UVB rays, it’s essential to choose a sunscreen that says “broad-spectrum” on the label—this indicates that the product helps protect against UVB and UVA rays. Both types of UV rays can damage your skin and contribute to skin cancer. As mentioned above, UVB rays are responsible for causing sunburns. UVA rays, on the other hand, are often referred to as “aging rays” because they can prematurely age your skin—resulting in fine lines, wrinkles, and discoloration. These rays may also damage your skin when you’re indoors.
According to the Skin Cancer Foundation, more than 50% of UVA rays can penetrate glass (whereas UVB rays are largely blocked by glass).3,4 And more than 80% of UVA rays can penetrate cloud cover, according to the American Academy of Dermatology.1 That’s why it’s so important to wear (and reapply) sunscreen every day, even when it’s cloudy or when staying indoors.
Where Can I Find My Sunscreen’s SPF Value?
The U.S. Food and Drug Administration (FDA) requires all sunscreen products to include an SPF number on their front labels. This SPF rating is determined using a standardized test set forth by the FDA. Sunscreen labels must also indicate whether or not the product has passed the required test to be considered a “broad-spectrum” sunscreen.
What SPF Number Should I Use?
Sunscreens with higher SPF numbers generally offer more protection against UVB rays than those with lower SPF numbers. Let’s use SPF 30 vs. SPF 50 as an example. When you apply a sunscreen with SPF 30, it will help reflect and/or absorb approximately 97% of UVB rays. Meanwhile, a sunscreen with SPF 50 will help reflect and/or absorb about 98% of UVB radiation, per the Skin Cancer Foundation.3 There are also sunscreens that contain an SPF value higher than 50, going all the way up to SPF 100.
What’s a Good SPF Value for Everyday Sun Protection?
There are a few factors to consider when choosing an appropriate SPF value for your daily needs. According to the FDA, only sunscreens with an SPF value of 15 or higher can be considered effective for helping to protect against early skin aging and skin cancer (when used as directed in addition to other protective measures).5 However, the American Academy of Dermatology and the Skin Cancer Foundation both recommend using a water-resistant, broad-spectrum product with an SPF of at least 30 for daily sun protection.1,3 When in doubt, it’s always best to consult a board-certified dermatologist, who can recommend the optimal sunscreen formula and SPF number for your specific needs.
Is a Higher SPF Always Better for Your Skin?
As mentioned earlier, sunscreens that have a higher SPF number generally offer more protection from the sun’s harmful rays. So, does this mean that you should look for a sunscreen with SPF 100 for the best protection? Not necessarily. The FDA says that sunscreens with a higher SPF number may provide greater sunburn protection, but this generally only applies to products with an SPF up to 50.5. The difference in protection between very high SPF numbers (above 50) is actually very small.
The Skin Cancer Foundation also explains that sunscreens with a very high SPF number may give people a false sense of security, leading them to apply (and reapply) less often or spend more time in the sun.3 Remember: A higher SPF does not mean you can spend more time outside without reapplying.
Sunscreen Tips
While the SPF number on your sunscreen label is important, it’s also essential to apply (and reapply) sunscreen correctly—in addition to other sun protection measures, like seeking shade and wearing protective clothing. Here are a few tips to keep in mind when choosing and applying your sunscreen.