What is UPF?

what is upf header

What Is UPF?

Whether you're out in the sun all day or only on occasion, protection from harmful UV rays is paramount. People are increasingly turning to ultraviolet protection factor clothing, as it helps prevent sunburns and the long-term effects of prolonged sun exposure, including sunspots, premature wrinkles and skin cancer.

In this guide, we'll discuss the definition of UPF and UPF clothing and examine how it compares to the better-known SPF standard. We'll also talk about the benefits of wearing one of the most popular UPF clothing items — hats.


little boy wearing bucket hat micrographic

Benefits of UPF

UPF is to clothing what sun protection factor is to sunscreen — it indicates the fraction of UV light that can penetrate a fabric. For instance, a 25 UPF rating means the fabric lets in 1/25, or 4%, of the UV radiation, and a garment with a UPF rating of 50 lets in 1/50, or 2%, of the UV radiation. 

The UPF clothing industry has seen remarkable growth in recent years, expanding from mainly practical items to a wider variety of attractive, everyday clothing styles. UPF clothing is now available in thousands of designs by dozens of companies, all of which use treated fabrics, tighter weaves or both to block UV rays more effectively. Some clothing manufacturers specialize in UPF apparel, including Coolibar, UV Skinz and Mott50. Other well-known brands, like Athleta and Uniqlo, also offer UPF items now. 

This surge in popularity is partly due to frustrations with sunscreen, which include its uncomfortable greasy feeling, the need to apply it frequently and the risk it may pose to aquatic life. Over recent decades, consumers have become more aware of the dangers of extended exposure to sunlight, which has also contributed to the growing popularity of SPF clothing. 


UPF protective clothing, like sunscreen, undergoes testing at independent laboratories, but UPF testing is currently not a requirement. Generally, companies that manufacture and sell UPF items in the United States follow complementary standards established by the American Association of Textile Chemists and Colorists and ASTM International, formerly known as the American Society for Testing and Materials. Clothing tags will often say the items have a UPF rating, but will not mention whether they have met those standards specifically.  

If the tag includes a Seal of Recommendation from the Skin Cancer Foundation, that shows compliance, but not all companies apply for the distinction. 

Laboratories use AATCC and ASTM protocols to gauge the percentage of UV radiation that penetrates a specific fabric. Some UV rays pass through to the skin directly via micro-spaces located between fibers, and the fibers will absorb or deflect other rays. Moisture can also affect a garment's UPF rating, with a dry fabric usually providing more protection than the same piece when it's wet.  

Recommended Ratings

Garments with UPF ratings below 15 are not sun-protective. To get the voluntary Seal of Recommendation from the Skin Cancer Foundation, the item must earn a 30 or higher rating from either the ASTM or AATCC. Any rating above 30 provides sufficient protection, though 50 is the best. While a UPF rating can technically be higher than 50, it won't offer significantly better protection, so garments with ratings above 50 will report it as "50+." 

UPF vs. SPF — What's the Difference?

UPF and SPF are both standards for measuring UV protection. Most everyone is familiar with SPF, which has measured sunscreen effectiveness for decades. In contrast, the UPF standard is relatively new and created specifically for rating UV protection offered by fabrics. Originally, sun-protective materials in the United States used SPF ratings, and the UPF standard didn't come into existence until later. Since applying for a UPF rating is not mandatory, many sun-protective clothing manufacturers continue to use the SPF standard.    

SPF Rating System 

Companies perform SPF testing on humans. SPF measures how long someone can stay under the sun before their skin starts to burn. For instance, if someone starts to get a sunburn after only 10 minutes, if they apply adequate sunscreen with an SPF 15 rating, the sunscreen should give them 150 minutes of sun protection. 

It's essential to note that, while sunblocks with the same SPF ratings will provide identical protection from UVB rays, no sunscreen protects you from all UVA rays. Even if a sunscreen claims to protect against UVA rays, the SPF standard currently doesn't measure protection from UVA rays. 

While researchers still believe UVB rays primarily cause sunlight-induced skin damage, particularly sunburn, many experts hypothesize UVA rays may be involved in other sun damage types, including wrinkles, aging and skin cancers. 

UPF Rating System 

Manufacturers of UPF fabrics don't test their effectiveness on human subjects. Instead, they usually use spectrophotometer tools. The UPF rating shows what percentage of UV radiation the clothing's fabric absorbs. 

For instance, a garment with a 50 UPF rating lets only 1/50th UV radiation from the sun go through it, meaning the garment will reduce your exposure to radiation by 98% in places the fabric protects. 

One advantage the UPF standard has over the SPF standard is that it measures protection against UVB and UVA rays.

why get a hat with upf protection


Why Get a Hat With UPF Protection?

If you're only going to invest in one clothing item with UPF protection, a hat is perhaps the best choice. Benefits of UPF hats include the following.

  • You can still be stylish: If you're new to UPF, you may not realize UPF hats come in a wide variety of styles, meaning you won't have trouble finding a hat design that suits your tastes. 
  • It provides better protectionUPF hats aren't only an alternative to sunscreen on your face — they offer better protection than sunscreen, as they shield you from UVA and UVB rays. 
  • There is no need to reapplyPut on your UPF hat and you're good to go — no need to reapply every few hours. 
  • You won't have to apply sunscreen on your children: If you're the parent of young children, you know how much of a struggle it can be to put sunscreen on them. Having them wear UPF hats will protect their face, ears and neck from harmful sun rays. 
  • There are no annoyances: By using a UPF hat instead of sunscreen, you don't have to deal with all the irritations associated with sunscreen — your skin won't feel greasy, you'll never have to experience the sting of getting sunscreen in your eyes and you won't have to worry about your protection washing off when you go in the water.   
  • They're a great choice if you suffer from photosensitivity: Sun sensitivity can result from skin care products, medical conditions and some medications. If you struggle with this condition, consider getting a hat with UPF protection next time you go out in the sun.     
  • They're more environmentally friendly: As we mentioned earlier, some chemicals used in sunscreens threaten marine life. By choosing SPF hats for your sun protection, you're not only benefiting yourself — you're helping Mother Nature. 

Best Hats With UPF Protection

As we mentioned above, UPF hats come in a broad array of styles and designs. Here are some of the most popular items for men. 

  • Henschel Aussie Packable Breezer® Safari Sun Hat: This high-quality safari sun hat boasts a UPF rating of 50+, meaning it protects you against 99% of the sun's ultraviolet rays. Its mesh crown is very breathable, and its canvas-wrapped brim is sufficiently wide to offer plenty of shade when doing activities like gardening, fishing, boating and hiking.
  • Down Under Leather Outback Hat: If you like outback hats, you'll love this durable, stylish hat made from UPF 50+ buffalo leather. This high-quality hat features a braided leather hatband and comes in black and dark brown color options. It's also easy to travel with, thanks to its crushable structure. Whether you're planning a hike in the mountains or a night on the town, this fashionable outback hat is a great choice. 
  • Adams Extreme Condition Hat: The Adams Extreme Condition Hat, which features a helpful neck flap, is perfect for extensive activities outdoors. Made from 30% nylon and 70% cotton, this hat provides UPF 50+ protection. It features a crown made of cotton and a three-inch brim.
  • Stetson Digger Shantung Straw Outback Hat: Made from stiff, durable shantung straw, the Stetson Digger is one of the best hats for spending time outdoors. Featuring a vented crown, this hat has a functional design and provides excellent UPF protection without sacrificing style. It also comes with an attractive leather band. 
  • Adams Extreme Performance Cap: This low-profile, four-panel baseball cap made of lightweight Rayosan UV-protective fabric boasts a wide array of features and a stylish baseball-style hat for outdoor enthusiasts. Its elongated bill provides extra shade. Other highlights include an under-brim for deflecting sun rays and glare, a comfortable terrycloth sweatband interior, Velcro closure to help with adjustability and mesh on both sides to make the hat more breathable. This cap is ideal for fishing, hiking or any other activity requiring breathable, lightweight material, sun protection and comfort. 
  • Dorfman Pacific Evergreen Supplex Boonie Bucket Hat: This durable outdoor hat features a big-brimmed bucket and offers 50+ UPF protection, making it an excellent choice for hiking, fishing, off-roading, boating or relaxing by the ocean.  

Women also have a wide assortment of SPF hat styles to choose from. The most popular women's style hats include the following.

kooringal ladies poly stripe
  • Kooringal Ladies Poly Stripe: The classic Ladies Poly Stripe from Kooringal has a crushable structure, making it perfect for bringing along on your next vacation. Made from lightweight polyester, this is a great choice if you need a hat that's casual, all-purpose and breathable. With a UPF rating of 50+, this hat also offers top protection against UV rays, and is available in a wide array of colors, allowing you to match it with any outfit.
  • Kooringal Ladies Reversible Golf HatThis reversible mid-brim golf hat from Kooringal is a cute hat for walking outside, going to the beach or, as the name suggests, golf. This hat also features a drawstring, which allows for size reduction if needed. This hat is reversible, crushable and boasts a 50+ UPF rating. 
  • Koorginal Bora Bora Straw Fedora Hat: The Bora Bora Straw Fedora Hat from Kooringal is easy to wear and a great item to take on trips, due to its easily crushable structure.  The crown's base features two lines of colorful beads and an extra black string you can use to adjust the size. The inside of the hat, though unlined, has an elasticized sweatband to help with sizing. The Bora Bora has excellent sun protection, with a UPF rating of 50.
  • Dorfman Pacific American Flag Rush Lifeguard Sun Hat: Featuring an American flag under the brim, this straw-woven lifeguard hat provides excellent protection against UV rays. It's also lightweight and features a four-inch-wide brim, making it an ideal choice for a sunny day by the sea or on the water. This hat is a stylish choice for men, too.
  • Kooringal Noosa Cotton Canvas Upturn Brim Hat: This cotton canvas hat, which features an upturned brim, offers a new take on sun hats. Whereas traditional sun hats are lightweight and made from straw, this hat is 100% cotton, making it exceptionally breathable and cool to wear. It also provides superior protection against UV rays, with a UPF rating of 50+. Its crushable structure also makes it easy to pack and travel with. 
Order a UPF hat from Hats Unlimited

Order a UPF Hat From Hats Unlimited

Over 25 years ago in Ventura, Calif., we founded Hats Unlimited with the mission to provide hats in as many styles, colors and varieties as possible. We attribute our business' success and longevity to our commitment to high-quality products and superior customer service. Over the years, our reach has expanded to areas throughout Southern California, with retail locations in Ventura, Santa Barbara, Palm Springs, La Jolla, Rancho Mirage, Solvang and Avila Beach. Due to our customers' demand to buy the hats they want from anywhere in the world, we launched hatsunlimited.com. 

All our stores boast more than 10,000 hats in stock, and our site has over 1,000 hat styles — and we're adding more every week. Our wide variety of options will ensure you'll have no trouble finding a hat that matches your needs and tastes. No matter what type of hat you're looking for — sports hats, women's fashion hats, kids' hats, funny hats, fedoras or Indiana Jones hats — you'll find it at Hats Unlimited.