Every day is a chance to take care of your skin—and wearing sunscreen is one of the most powerful skincare habits you can build. But with so many symbols, acronyms, and claims on the label, it’s easy to feel a little lost. That’s why we’ve created this simple, science-backed sunscreen glossary—to help you confidently decode your sunscreen and choose the protection that’s right for your skin.
Whether you’re a skincare enthusiast or just starting your sun protection journey, this guide has everything you need to know. Let’s dive in.
First things first: key sunscreen facts to know
Let’s start with some FAQs using guidance from the American Academy of Dermatology (AAD). These are the essential terms you’ll see on almost every sunscreen bottle.
What does SPF mean?
SPF stands for Sun Protection Factor. And contrary to popular belief, it’s not a measurement of time, but instead, an amount. To sum up the science, it measures the amount of solar energy needed to burn unprotected skin.
The number refers to how well your sunscreen helps protect your skin from UVB rays versus if you went without it. As the SPF number increases, so does your protection against sunburn.
However, a high number doesn’t mean you’re in the clear. The amount of SPF skin protection also depends on your skin type, how strong the sun is, and how frequently you apply (the right amount of) sunscreen.
Pro tip: Opt for SPF 30 or higher—that’s what dermatologists recommend for daily use.
UVA vs. UVB protection
Both types of ultraviolet radiation can be harmful, but they act differently:
- UVA rays penetrate deeper into the skin and are linked to premature aging (AKA photoaging) and some skin cancers. They can also reach your skin indoors.
- UVB rays mostly affect the surface layers, causing sunburns and increasing skin cancer risk. They’re at their strongest when your shadow’s at its smallest (i.e. peak summertime).
The good news? A broad spectrum sunscreen protects you from both.
Speaking of, what is broad spectrum sunscreen?
Broad spectrum means the sunscreen shields your skin from both UVA and UVB rays. This is a critical label to look for—it’s the only type of sunscreen the AAD recommends. If it doesn’t say broad spectrum, it’s not giving you complete protection.
Mineral vs. chemical sunscreen
The main difference lies in how they filter UV rays:
- Mineral (AKA physical) sunscreens use ingredients like zinc oxide and titanium dioxide to physically reflect rays off the skin.
- Chemical sunscreens capture UV rays, convert them into heat, and expel them back out.
Both types are effective, and some formulas even combine both.
Want to learn all the ins and outs? Check out our full guide on mineral vs. chemical sunscreens.
Water-resistant sunscreen
Spoiler alert: No sunscreen is truly waterproof. If a product is water-resistant, it means its SPF was tested to remain effective after 40 or 80 minutes in water or while sweating.
Always check the label—and reapply regularly, especially after swimming, sweating, or towel drying.
Your sunscreen glossary: A to zinc
Here’s your go-to guide to decoding your sunscreen label—including a few extra features and ingredients along the way. Use it while you shop, apply, or refresh your routine.
360° protection
ISDIN’s holistic approach to sun protection offers all-around care for daily exposure to environmental factors. It’s designed to combat both photoaging and pollution, plus damage from blue light, heat, and free radicals.
Actinic damage
Damage caused by long-term UV exposure, especially from the sun. Signs can include fine lines, sun spots, and an increased risk of more serious concerns such as actinic keratosis or skin cancer. Daily sunscreen use is key to prevention.
Active ingredient
These are the UV filters that work to protect your skin. On the label, you’re likely to find ingredients like zinc oxide, avobenzone, or octocrylene.
Antioxidants
Vitamin E, botanical extracts—antioxidants in sunscreen help to support skin’s natural defenses and fight the effects of daily environmental stressors.
Broad spectrum
As covered above, this label means the sunscreen shields against both UVA and UVB rays. It’s a must-have for full sun protection.
DNA Repairsomes®
Plankton-derived technology that helps repair existing sun damage. Found in innovative formulas like Eryfotona Actinica and Eryfotona Ageless.
Drug Facts
In the US, sunscreens are regulated by the FDA as over-the-counter (OTC) drugs. The label’s Drug Facts panel lists active ingredients and usage directions—always a must-read.
Facial sunscreen
Specifically formulated for the delicate skin on your face—often lighter, non-comedogenic, and more targeted than body sunscreens. Choose one that suits your skin type for everyday wear.
Mineral sunscreen
A sunscreen that uses natural minerals (like zinc oxide) to deflect UV rays from the skin’s surface. Sometimes preferred by those with very sensitive skin.
Non-comedogenic
This means the product is formulated not to clog pores, making it ideal for blemish-prone or oily skin. ISDIN’s facial sunscreens are non-comedogenic and suitable for all skin types.
Peptides
Short chains of amino acids that support skin repair and firmness. You’ll find them in some expert sunscreens that combine protection with skincare.
Photoaging
The visible signs of aging caused by sun exposure. Think fine lines, dark spots, rough texture—daily sunscreen (especially a targeted formula) is your best defense.
SPF (Sun Protection Factor)
The measure of UVB protection your sunscreen offers. Remember: SPF 30 blocks about 97% of UVB rays, and SPF 50 blocks about 98%. Reapply at least every two hours, no matter the number.
Sunscreen for oily skin
Lightweight, non-greasy, and non-comedogenic formulas that won’t clog pores—like ISDIN facial sunscreens.
Sunscreen for sensitive skin
Gentle formulas that are tested on all skin types and recommended by dermatologists. Oftentimes, mineral-based formulas are the ideal option.
Water-resistant
Indicates the sunscreen has been tested to remain effective after water exposure—usually for 40 or 80 minutes. Still, reapplying is key after swimming, sweating, or towel drying.
Zinc oxide
A mineral UV filter used in physical sunscreens. Known for its excellent sun protection, especially for sensitive or blemish-prone skin.
How to read your sunscreen label: the final checklist
When choosing your sunscreen, here are the must-haves to look for:
- SPF 30 or higher
- Broad spectrum protection
- Non-comedogenic
- Dermatologist tested
- Additional features like water resistance or antioxidant action? Bonus!
Now that you know the ins and outs of your sunscreen label, you’re better equipped to care for your skin with intention—every single day. Choose the formula that works best for you, apply generously, and reapply often. Because it all comes down to protecting what matters most: your skin, your health, and your joy.