UPF – SPF – UV? Know the Difference. Stay Protected.

Learn the difference between the terms UPF, SPF, and UV, and how to stay protected from the sun's rays on the UV Skinz's blog.
UV Rays Chart

When you hear statistics like “95% of skin cancers can be prevented” and that “one major sun burn as a child can put a person at risk for skin cancer”, it becomes even more important to have a solid understanding of skin cancer prevention.

What's the Difference Between UPF, SPF, and UV?

UPF and SPF seem to get tossed around and are often used interchangeably but the way they work is very different. Understanding those differences will help you become a sun protection warrior ready to defend yourself and your kids against the dangers of the sun.

UV Defined

UV – Ultraviolet (UV) radiation is found in invisible rays that come from sunlight; overexposure to UV rays can lead to sunburn, accelerated skin aging, and skin cancer. UPF clothing and sunscreen offer your main forms of UV protection. There are actually two types of UV rays we need to be concerned with, which are explained below.

UV rays

UVA – UVA rays are the long rays which can penetrate deep into the skin and can also penetrate through most fabrics. These rays causes premature skin aging, wrinkling and potentially skin cancer. They also penetrate skin more deeply than UVB rays. UVA rays are harmful during any hour of daylight and aren’t blocked by clouds, fog, or untreated glass.

UVB – UVB rays are the short rays, which are seen as direct sun light. They cause sunburn, contribute to premature skin aging, and potentially skin cancer. UVB rays are the strongest between 10am and 4pm. They can penetrate clouds and fog, but not glass.


UPF Defined

UPF – Ultraviolet Protection Factor (UPF) is a rating system used for clothing. It indicates how effectively fabrics shield skin from ultraviolet rays (both UVA and UVB).

The higher the UPF number, the greater degree of UV protection a garment offers. UPF 50 + clothing blocks 98% of harmful rays and does not contain chemicals that will wash out in the water or laundry.

SPF Defined

SPF – Sun Protection Factor is the rating system used for sunscreen products. An SPF number pertains only to a sunscreen’s effectiveness against UVB rays, the sunburn-causing segment of the ultraviolet spectrum.

A broad-spectrum sunscreen will help protect you against both UVA and UVB rays. Sunscreens need to be reapplied often to be effective.

UPF Versus SPF: What’s The Difference?

UPF vs SPF – SPF sunscreen uses chemicals to absorb UVB rays. Some of these chemicals absorb into the skin. UPF clothing absorb or reflect UVA and UVB rays, and wearing them does not transfer any chemicals to the skin.

This means that if you’re in the sun and wearing SPF sunscreen on your arms and face, those areas might be protected from UVB rays but your whole body is exposed to harmful UVA rays unless you’re wearing a broad-spectrum sunscreen.

Wearing clothing that has a rating of UPF 50+ means the solar radiation is blocked, throughout the day. Wearing a UPF hat will protect your face and forehead from harmful radiation whereas UPF pants and shirts will protect 90% of the body skin from UVA and UVB radiation.

Staying Protected with UV Skinz's UPF 50+ Swimwear

Ever wonder why our certified UPF 50+ swimwear protects you so well? Our fabric has a special, tightly woven construction that blocks 98% of the sun’s harmful UVA and UVB rays. With UV Skinz you’ll have “peace-of-mind in the sun” knowing you’re wearing the best protection possible.