How to Read SPF Labels on Sunscreens

How to Read SPF Labels on Sunscreens

Hey FaceTory Fam 💝

We’re talking sunscreen today!

We get it, it can get a little confusing with all those acronyms and terms on packaging 😅 So today, we’re going to help you decode the labels on sunscreen! Read on to learn more!  🤗

First, let’s talk UV. UV stands for ultraviolet radiation. The 2 types that affect the skin in a negative way are UVA and UVB. The sun’s energy is extremely strong and is present in these invisible rays that can burn your skin and cause skin cancer. 
Like, really. Don’t underestimate the sun 😳 


  • Ultraviolet A
  • Has longer rays than UVB and is deeply penetrating
  • UVA rays can also penetrate through glass windows (Yikes! Be sure to wear sunscreen even if you’re staying indoors)
  • An easy trick to remember this is UVA= Aging. Because UVA rays can penetrate deeply, these rays affect the dermis and can cause DNA damage and can speed up signs of aging. 


  • Ultraviolet B 
  • Causes sunburn and are believed to cause the majority of skin cancers
  • An easy trick to remember this is UVB= Burning. UVB rays are shorter rays that can penetrate the epidermis and can cause sunburn and contribute to causing the majority of skin cancers  

    Now, you know of the sun’s rays, we can break down the labeling system:


    • Sun Protection Factor
    • This only deals with UVB part of the ultraviolet energy that comes from the sun
    • It measures how long you can stay out in the sun without burning
    • The number that follows SPF tells you how much UVB light it filters
    SPF 15 blocks 93%- 95%
    SPF 30 blocks 97%
    SPF 50 blocks 98%
    • Or you can read it based on time instead of formula. For instance:
    • If it takes you 10 minutes of direct sun exposure for your skin to turn red, applying an SPF 15 sunscreen will give you 150 minutes of sun protection. (SPF15 x 10 minutes= 150 minutes)
    • Note: Skin can become inflamed and cellular damage can develop long before the skin turns red. That being said, your best bet for protection is looking for Broad Spectrum.

    Broad Spectrum

    • A sunscreen that filters both UVA and UVB
    • Zinc Oxide and Titanium dioxide reflect both sections of the spectrum 


    • Persistent Pigment Darkening
    • Focuses on UVA exposure only. 
    • Determines the time it takes for skin to tan compared to if it was unprotected.
    • Mainly used in Asia and Europe


    • Rates the amount of the UVA protection a product offers
    • Mainly used in Asian countries

    Overall, you want to make sure you are protecting your skin from UVA and UVB rays. Having a broad-spectrum sunscreen will allow you to protect the outermost layer of your skin all the way down to the inner layers of your skin. So please don’t forget to include sunscreen into your skincare routine and apply + reapply! 

    Thanks for reading!


    FaceTory 💝