SPF and UPF both describe protection from ultraviolet radiation, but they apply to different forms of sun protection. SPF, or Sun Protection Factor, is used for sunscreen. UPF, or Ultraviolet Protection Factor, is used for clothing and other textiles.
The numbers may look similar, but SPF 50 and UPF 50 do not mean exactly the same thing. They come from different testing systems and should not be compared as if they were interchangeable ratings.
What Is the Difference Between SPF and UPF?
The simplest difference is what each rating measures. SPF describes the sunburn protection provided by sunscreen when it is applied and used as directed. UPF describes how effectively a textile reduces ultraviolet radiation passing through the material to the skin beneath it.
- SPF: used for sunscreen applied to the skin.
- UPF: used for clothing and other textiles.
Both can form part of the same sun-protection strategy. Clothing can cover larger areas of the body, while sunscreen can protect skin that remains exposed.
What Does SPF Mean?
SPF stands for Sun Protection Factor. It measures the relative amount of ultraviolet exposure required to produce sunburn on sunscreen-protected skin compared with unprotected skin.
A higher SPF represents greater protection against sunburn when the sunscreen is used correctly. The SPF value primarily indicates protection against UVB radiation, although UVA can also contribute to sunburn. Sunscreens labelled broad spectrum provide protection across both UVA and UVB radiation.
One common misconception is that SPF represents time. SPF 30 does not mean you can simply stay in the sun 30 times longer without burning. UV exposure depends on factors including solar intensity, time of day, location, cloud conditions and how the sunscreen is used.
For a deeper explanation of sunscreen itself, see our guide to how sunscreen works.
What Does UPF Mean?
UPF stands for Ultraviolet Protection Factor. Instead of rating sunscreen, it describes how effectively a textile reduces ultraviolet radiation reaching the skin beneath it.
A UPF 50 fabric allows approximately 1/50th of the relevant ultraviolet radiation to pass through the material. In practical terms, that corresponds to about 2% transmission, or approximately 98% being blocked by the rated material.
The UPF rating applies to the material and the area of skin it covers. It does not protect exposed areas such as the face, hands or uncovered parts of the neck.
For a more detailed explanation of the rating itself, including the meaning of the plus sign, read what UPF 50+ means. If you want to understand how fabric construction, stretch, wetness and other characteristics influence textile protection, see how UPF clothing works.
SPF vs UPF at a Glance
- SPF applies to: sunscreen.
- UPF applies to: clothing and textiles.
- SPF primarily measures: protection against sunburn, with the SPF value primarily reflecting UVB protection.
- Broad-spectrum sunscreen: provides protection across both UVA and UVB radiation.
- UPF measures: how effectively a textile reduces ultraviolet radiation passing through to covered skin.
- Both ratings: describe UV protection, but they are determined differently and are not interchangeable.
Is UPF 50 the Same as SPF 50?
No. UPF 50 and SPF 50 are not equivalent ratings, even though both contain the number 50.
UPF 50 describes UV transmission through a textile. A UPF 50 material allows approximately 1/50th of the relevant ultraviolet radiation to pass through it. SPF 50 is determined using a different testing method that compares the UV exposure required to produce sunburn on sunscreen-protected and unprotected skin.
The matching numbers should therefore not be interpreted as meaning that an SPF 50 sunscreen and a UPF 50 garment provide identical protection in identical ways.
Does SPF Protect Against UVA and UVB?
The SPF value primarily indicates protection against sunburn and therefore primarily reflects UVB protection. To identify sunscreen that also provides UVA protection, look for a broad-spectrum claim that meets the applicable regulatory standard.
This distinction matters because UVA and UVB affect the skin differently. Both forms of ultraviolet radiation can damage the skin, which is why broad-spectrum protection is important when choosing sunscreen.
Does UPF Protect Against UVA and UVB?
UPF testing evaluates textile protection across the relevant ultraviolet spectrum rather than describing protection against only UVB. The resulting rating indicates how effectively the tested textile reduces ultraviolet radiation reaching covered skin.
The protection provided by a garment still depends on the rated material actually covering the skin. The behaviour of some textiles can also change with factors such as stretch, moisture and wear.
Is UPF Better Than SPF?
Neither is inherently better because they perform different jobs. UPF-rated clothing protects covered skin, while sunscreen is applied directly to the skin and is particularly useful for areas that clothing does not cover.
Clothing has a practical advantage in that properly covered areas remain physically covered without requiring sunscreen to be repeatedly spread across the same skin. However, a garment only protects the areas it covers, and its protection depends on the textile and condition of the garment.
Sunscreen can protect exposed areas that clothing cannot practically cover, but its real-world performance depends on correct application and reapplication according to the product instructions.
Can UPF Clothing Replace Sunscreen?
UPF clothing can reduce the amount of skin that needs sunscreen, but it does not remove the need to protect uncovered areas.
For example, a long-sleeve UPF shirt can cover much of the torso and arms. The face, hands, parts of the neck and any other exposed skin still require appropriate protection.
A broader sun-protection strategy can combine protective clothing with shade, appropriate headwear, sunglasses and broad-spectrum sunscreen on exposed skin.
Do You Need Sunscreen Under UPF Clothing?
The priority is to protect skin that is not adequately covered by protective clothing. If a garment provides reliable UPF protection and fully covers an area of skin, sunscreen beneath that covered area is generally less important than protecting the skin that remains exposed.
The more important consideration is whether the garment actually provides the expected coverage and protection. Fit, fabric condition and the way the garment is worn can all matter. Sunscreen should still be used on exposed skin according to the product instructions and relevant sun-safety guidance.
Why SPF and UPF Matter Around Water
Sun protection becomes particularly relevant around the coast because surfing, kitesurfing, swimming and other watersports can involve long periods outdoors with limited access to shade.
The combination of clothing and sunscreen becomes easy to understand in real watersports environments. At Poetto Beach in Sardinia, extended time around the coast can involve alternating between time in the water and time on exposed shoreline. At Dakhla, long watersports sessions can similarly mean spending substantial periods outdoors. In both situations, covered skin and exposed skin require different forms of protection.
These destinations are examples rather than fixed sun-protection recommendations. UV intensity varies with location, season, time of day, cloud cover and atmospheric conditions, so current local conditions and the UV Index should always be considered.
Water and other bright surfaces can contribute to reflected UV exposure. Swimming, sweating and physical activity can also affect sunscreen, which is why the product's water-resistance claim and reapplication instructions matter during watersports.
Protective clothing can reduce the amount of exposed skin during a long session. Sunscreen can then be used on areas that remain uncovered. Rather than choosing between SPF and UPF, the two can complement each other.
Does All Clothing Have a UPF Rating?
No. Most clothing blocks at least some ultraviolet radiation, but not every garment has been tested and labelled with a UPF rating.
The amount of protection provided by ordinary clothing varies with factors such as fabric density, construction, colour, stretch, wetness and wear. A UPF rating gives more specific information because the textile has been evaluated for UV protection according to an applicable testing method.
What Affects UPF Protection?
The protection provided by a textile is influenced by more than its fibre composition. Fabric density and construction, colour, stretch, wetness, wear and the amount of skin covered can all influence real-world protection.
This is why a nylon or polyester shirt should not automatically be assumed to provide a particular UPF rating based only on its fibre composition. For the full explanation, see how UPF clothing works.
What Affects SPF Protection in Practice?
The number printed on a sunscreen is only useful when the product is used correctly. Real-world protection can be affected by how much sunscreen is applied, whether areas are missed, swimming, sweating, rubbing and reapplication.
For time around the water, the sunscreen's broad-spectrum and water-resistance claims are particularly relevant for exposed skin. Follow the instructions on the specific product for application and reapplication.
How SPF and UPF Work Together in Waterwear
SPF and UPF are easiest to understand as different layers of protection rather than competing ratings. UPF-rated clothing can provide coverage across larger areas such as the torso and arms, while sunscreen can protect skin that remains exposed.
For active watersports, the garment itself also needs to suit the activity. Fit, stretch, freedom of movement, drying characteristics and coverage remain important alongside its UPF rating.
The Water Peak's Performance-Fit Coastech™ Rashguard combines UPF 50+ protection with a close second-skin performance fit, while the Regular-Fit Visibility Water Shirt provides UPF 50+ protection in a more relaxed performance fit.
Neither garment removes the need to protect exposed skin. The practical role of UPF-rated waterwear is to reduce the amount of skin directly exposed while providing a garment designed for movement in and around water.
Frequently Asked Questions
What is the main difference between SPF and UPF?
SPF is a rating used for sunscreen, while UPF is a rating used for clothing and textiles. They both relate to UV protection, but they measure different forms of protection using different testing methods.
Is SPF 50 equal to UPF 50?
No. SPF 50 and UPF 50 are not directly equivalent. UPF 50 describes UV transmission through a textile, while SPF 50 describes the relative sunburn protection provided by a sunscreen under its testing method.
Should I use SPF or UPF at the beach?
They can be used together. Protective clothing can cover larger areas of skin, while broad-spectrum sunscreen can be applied to areas that remain exposed.
Do I still need sunscreen when wearing UPF 50+ clothing?
Exposed skin still requires appropriate protection. UPF clothing only protects the area covered by the garment, so areas such as the face, hands and uncovered parts of the neck may still require sunscreen or another appropriate form of protection.
Does a normal T-shirt have UPF protection?
Most clothing provides some UV protection, but the amount varies considerably. Without a tested UPF rating, the exact level of protection cannot be determined simply from the fact that a garment covers the skin.
SPF and UPF Protect in Different Ways
SPF and UPF protect against ultraviolet radiation in different ways. SPF applies to sunscreen and primarily indicates protection against sunburn, while UPF describes how effectively a textile reduces ultraviolet radiation reaching covered skin.
One does not make the other unnecessary. Around the coast and on the water, protective clothing can reduce the amount of exposed skin, while broad-spectrum sunscreen can protect the areas that remain uncovered.
Understanding the difference makes it easier to use each form of protection for the job it is designed to do.