What is the Difference Between SPF and PA+++

Sun protection is the shield against the sun’s damaging rays. Sun protection helps prevent sunburn, premature aging, and even skin cancer. SPF and PA+++ are needed to protect the skin against the harmful rays of the sun.

What is the difference between SPF and PA+++? SPF, or Sun Protection Factor, measures protection against UVB rays, while PA, or Protection Grade of UVA, measures protection against UVA rays.

Key Areas Covered

1. What is SPF  
      – Definition, Features 
2. What is PA+++
      – Definition, Features 
3. Similarities Between SPF and PA+++
      – Outline of Common Features
4. Difference Between SPF and PA+++
      – Comparison of Key Differences
5. FAQ: SPF and PA+++
      – Answers to Frequently Asked Questions

Key Terms

SPF, PA+++, Sun Protection Factor, Protection Grade of UVA

Difference Between SPF and PA+++ - Comparison Summary

What is SPF (Sun Protection Factor)

SPF measures how well a sunscreen provides protection from UVB rays, which are primarily responsible for sunburn and can contribute to skin cancer. SPF measures the time it would take for UVB rays to damage the skin with sunscreen compared to without. A higher SPF number indicates greater protection against UVB rays. For instance, sunscreen with SPF 30 means the burning of the skin is 30 times longer than the bare skin without sunscreen with SPF.

SPF and PA+++

What is PA (Protection Grade of UVA)

The PA rating system measures the level of protection against UVA rays, which penetrate deeper into the skin, causing premature aging and contributing to skin cancer. The PA rating ranges from PA+ to PA++++, with more pluses indicating higher protection. PA++++ offers the highest level of UVA protection currently available.

Similarities Between SPF and PA+++

  1. SPF and PA are two ratings regarding sun protection.
  2. Both SPF and PA ratings are essential for comprehensive sun protection.

Difference Between SPF and PA+++


  • SPF (Sun Protection Factor) protects against UVB rays, while PA+++ (Protection Grade of UVA) protects against UVA rays.


  • SPF is measured on a numerical scale (SPF 15, 30, 50+, etc.), whereas PA+++ is measured on a plus sign system (PA+, PA++, PA+++, PA++++).

Mechanism of Action

  • SPF absorbs or reflects UVB rays before they can damage skin cells. PA+++ doesn’t directly block UVA rays but rather helps prevent them from damaging skin cells. It achieves this through ingredients that absorb UVA rays or help neutralize the free radicals they generate.


Understanding the difference between SPF and PA+++ is essential for selecting the right sunscreen. PA++++ sunscreens are most effective at protecting from UVA rays, while sunscreens with an SPF of 30 or higher are best for UVB protection.

FAQ: SPF and PA+++

1. What is SPF?

SPF is the Sun Protection Factor,  Which measures how well a sunscreen provides protection from UVB rays, which are responsible for sunburn and can contribute to skin cancer.

2. What is broad-spectrum sunscreen?

Sunscreen which provides protection against both UVA and UVB rays the rays which causes skin damage the and contribute to skin cancer.

3. Does PA++++ prevent tan?

PA++++ sunscreen offers high protection against UVA rays, which are a major contributor to tanning. However, it won’t completely prevent tanning.

4. Which is better, PA+++ or PA++++?

PA++++ sunscreen offers better UVA protection than PA+++. Choosing between PA+++ and PA++++ depends on several factors, like sun exposure, skin type, and individual needs.

5. What are UVA Rays and UVB Rays?

UVA rays penetrate deeply into the skin and are a major cause of premature aging and wrinkles. They can also contribute to skin cancer. UVA rays can pass through window glass, so protection is important even indoors. On the other hand, UVB rays are responsible for sunburn and play a significant role in developing skin cancer. The SPF number on sunscreen mainly indicates the level of protection against UVB rays.

6. What does sunscreen contain?

Sunscreen contains both organic and inorganic chemicals.  Inorganic chemicals include minerals like zinc oxide and titanium dioxide, which act as physical sunblocks. They reflect UV rays away from the skin. Meanwhile, organic chemicals are ingredients like oxybenzone and avobenzone, which absorb UV radiation and release it as heat. These chemicals help prevent UV radiation from penetrating the skin and causing damage.

7. What is a “broad spectrum” sunscreen?

A “broad spectrum” sunscreen offers protection against both UVA and UVB rays. This is important because both types of rays can damage the skin and contribute to skin cancer. Broad-spectrum sunscreens ensure comprehensive protection by covering the entire UV spectrum.


1. “Ask the Expert: Does a High SPF Protect My Skin Better?” Sun & Skin News.
2. “PA ++++ In Sunscreen: What It Means & Why It Matters.” Color Science.

Image Courtesy:

1. “A Commercial Shot of SPF 50 Sunscreen” (CC0) via Pexels

About the Author: Hasini A

Hasini is a graduate of Applied Science with a strong background in forestry, environmental science, chemistry, and management science. She is an amateur photographer with a keen interest in exploring the wonders of nature and science.

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