Pick up any sunscreen or sunblock and you'll see a number: SPF 30, 50, 70, sometimes even 100. It's easy to assume a bigger number means all-day protection, but that's not quite how it works. Here's what SPF actually means, and how to choose the right sunscreen for Pakistan's strong sun.
What does SPF stand for?
SPF stands for Sun Protection Factor. It measures how well a sunscreen protects your skin from UVB rays, the part of sunlight that causes sunburn and contributes to tanning and skin damage. It is tested in a lab using a set amount of sunscreen and compares how long protected skin takes to redden versus unprotected skin.
What the SPF numbers mean
SPF numbers don't rise in a straight line. Each step up adds a little more protection:
| SPF | Approximate UVB blocked |
|---|---|
| SPF 15 | About 93% |
| SPF 30 | About 97% |
| SPF 50 | About 98% |
Two important points follow from this:
- Higher SPF does not mean you can stay out longer without reapplying. Sweat, rubbing and time break sunscreen down, so every SPF needs reapplying about every two hours outdoors.
- The amount you apply matters as much as the number. Lab tests use a generous layer. Most people apply far less, which lowers the real protection. A higher SPF gives you some margin for that.
UVA vs UVB: why SPF isn't the whole story
- UVB rays burn the outer layer of skin. SPF measures protection against these.
- UVA rays reach deeper. They drive tanning, dark spots and early wrinkles, pass through clouds and window glass, and are present all year round.
Both UVA and UVB contribute to skin cancer risk. Because SPF only measures UVB, always choose a sunscreen labelled broad spectrum, which means it also protects against UVA.
Why SPF matters in Pakistan
Much of Pakistan sees a very high to extreme UV index from spring to autumn, and even winter days in the plains usually reach a level where sun protection is recommended. Unprotected sun exposure leads to:
- Sunburn and tanning
- Dark spots, acne marks that won't fade, and uneven tone
- Early fine lines and loss of firmness
- Dull, dehydrated-looking skin
Which SPF should you use?
- Mostly indoors or short trips outside: SPF 30 or higher, broad spectrum. UVA still comes through windows.
- Commuting, outdoor work or long days out: SPF 50 or higher, and reapply every two hours.
- Northern areas, snow, water or sports: the highest SPF you'll wear comfortably. Altitude and reflections from snow and water raise UV a lot.
Deciding between the two highest options? Read SPF 50 vs SPF 70: which do you need in Pakistan? And yes, you need it in the cold months too: see why oil-free sunscreen is important in winter.
What to look for in a good sunscreen
- Broad spectrum (UVA and UVB)
- SPF 30 or higher
- Non-greasy or oil-free, especially for oily or acne-prone skin
- Light enough that you'll wear it every day
- No white cast on brown skin
Our Sunscreen SPF 70 is broad spectrum, lightweight and non-greasy, with no white cast, and made for Pakistani skin and weather.
How to apply sunscreen properly
- Make it the last step of your morning routine, after moisturiser and before makeup.
- Use about two finger-lengths for your face and neck.
- Apply 15 minutes before going out.
- Don't forget your ears, the back of your neck and the backs of your hands.
- Reapply every two hours outdoors, and after sweating or swimming.
Frequently asked questions
Is SPF 30 or SPF 50 better?
SPF 50 blocks slightly more UVB (about 98% vs 97%). Both work well if applied generously and reapplied. SPF 50 is the better pick for long hours in Pakistan's sun.
Is SPF 70 better than SPF 50?
It offers a little more UVB protection and more margin if you apply too thinly. It does not mean you can skip reapplying.
Is sunscreen the same as sunblock?
In everyday use, yes. People in Pakistan use both words for the same thing. What matters is broad-spectrum protection and the SPF number.
Do I need sunscreen indoors?
If you sit near windows, yes. UVA passes through ordinary glass.
This article is for general information and is not medical advice.