Clothing and hats are among the simplest and most effective ways to guard your skin from the sun’s harmful rays. They provide a physical block between your skin and the sunlight, and because clothes don’t wash or wear off, you won’t have to worry about reapplying, as you do with sunscreen.

In recent years, clothing manufacturers have also begun adding chemicals and additives to clothing during the production process to further boost the sun-protective factor.

High-Tech Sun Protection

More and more clothing and outdoor companies are carrying garments promoting an Ultraviolet Protection Factor (UPF). These clothes are treated with colorless dyes or chemical UV absorbers that block both ultraviolet-A (UVA) and ultraviolet-B (UVB) rays. UPF is similar to the Sun Protection Factor (SPF) that is used on cosmetics and sunscreens, but SPF only measures how much ultraviolet-B (UVB) is blocked; it does not measure UVA.

UPF Ratings

The American Society for Testing and Materials developed standards for labeling garments as “sun-protective.” A 30 is necessary for the product to be given the Skin Cancer Foundation’s Seal of Recommendation, and only clothes with a UPF of 15 to 50+ can be sold as “sun-protective.”

  • “Good”—indicates clothes with a UPF of 15-24
  • “Very Good”—indicates clothes with a UPF of 25-39
  • “Excellent”—indicates clothes with a UPF of 40-50

A UPF rating of 50 indicates the fabric will allow 1/50th—or about two percent—of the ultraviolet radiation from the sun to pass through to your skin. The higher the UPF number, the less light reaching your skin. 

Factors That Determine Sun Protection

All clothing disrupts UV radiation, even if only in small amounts. When determining a piece of clothing’s UPF, several aspects are taken into consideration. These factors also can be used by anyone to determine if a regular piece of clothing is efficient at blocking UV rays.


Dark-colored clothing is better than lighter shades, but the real blocking power comes from the type of dye used to color the fabric. The higher the concentration of certain premium UV-blocking dyes, the more rays they disrupt.


Cotton, rayon, flax, and hemp fabrics are not very effective at blocking UV rays, unless treated with an added chemical. Fabrics that are better at blocking the sun: polyester, nylon, wool, and silk.


Clothing that stretches may have less UV protection than clothing that doesn't stretch.


Clothing manufacturers may add chemicals that absorb UV light to clothing during the manufacturing process. Laundry additives, such as “optical brightening agents” and UV-disrupting compounds, can increase a garment’s UPF rating.


Loosely woven fabrics provide less protection than tightly woven fabrics. To see how tight the weave on a piece of clothing is, hold it up to a light. If you can see light through it, the weave may be too loose to be effective at blocking the sun’s rays.


The heavier the fabric, the better it is at blocking UV rays.


Dry fabric provides more protection than wet fabric. Wetting a fabric reduces its effectiveness by as much as 50 percent.

High-UPF Clothing

Recognizing the need for a variety of sun-protective clothing options, retailers are carrying greater numbers of clothing styles with high UPFs.

Some companies use a trademarked name to denote their sun-protective clothing. For example, Columbia’s high-UPF clothing is called “Omni-Shade.” The North Face, however, just notes the amount of UPF a product has in its description.


A white cotton t-shirt has between UPF 5 and UPF 8; it allows almost one-fifth of UV radiation to pass through to your skin. Better t-shirt options include:

To boost air circulation and help you stay cool, some tightly constructed UPF-garments use vents or holes. Others may be constructed with moisture-wicking fabric that helps pull sweat away from the body.

Pants or Shorts

Pants with a high UPF are a great way to protect your skin while you work, play, or relax. (If you wear shorts, don’t forget to apply sunscreen to the lower half of your legs.) Options include:


Swimsuits made with UV-protective, chlorine-resistant material block at least 98 percent of UV rays. High-UPF swimsuit retailers include:


Hats with a wide brim or neck shade (a piece of fabric which drapes over your neck) reduce the amount of exposure your delicate facial skin has to endure. Wearing one while outside will help reduce your UV exposure. Options include:

Making Your Clothes High-UPF

If adding sun-protective clothing to your wardrobe is cost prohibitive, or your children are growing too quickly to invest in clothes they won’t be able to wear in a few months, a sun protective colorless additive may be a great alternative to buying new clothes. For example, SunGuard Detergent, a UV blocking additive that is added to your laundry during a wash cycle, gives clothing an SPF factor of 30. The additive lasts up to 20 washes.

Many detergents contain OBAs (or “optical brightening agents”). Repeated laundering with these detergents will boost a garment’s UV protection.