SPF30 or SPF50? The numbers make SPF50 sound dramatically stronger, but both provide a high level of UVB protection. Applied correctly, SPF30 filters around 97% of UVB radiation, while SPF50 filters around 98%.
In practical terms, that means around 3.3% of UVB reaches the skin with SPF30 compared with around 2% with SPF50. SPF50 provides additional protection, but the difference is much smaller than the numbers 30 and 50 might suggest.
So which should you choose? For many situations, SPF30 provides excellent protection when used properly, while SPF50 gives you an additional margin of protection when UV exposure is higher or your skin is particularly sun-sensitive.
What's Inside
Is SPF50 much better than SPF30?
Not dramatically. SPF30 filters around 97% of UVB radiation, while SPF50 filters around 98% when applied correctly.
That means roughly 3.3% of UVB reaches the skin with SPF30 compared with around 2% with SPF50. SPF50 therefore provides additional protection, but both filter the vast majority of UVB.
For many people, SPF30 is an excellent everyday choice. SPF50 can be useful when UV levels or exposure are higher, or when you simply want the higher level of protection.
What does SPF actually mean?
SPF stands for Sun Protection Factor. It measures a sunscreen's ability to protect your skin from UVB radiation – the wavelengths most closely associated with sunburn.
SPF can also be understood as a measure of how much more UV exposure protected skin can tolerate before burning compared with unprotected skin. Under controlled testing conditions, SPF30 means it takes around 30 times as much UV exposure to produce the same level of sunburn as it would without sunscreen.
In real life, sun intensity changes throughout the day and sunscreen can be affected by swimming, sweating, towelling and how generously it's applied. That's why sunscreen still needs to be applied properly and reapplied according to the product instructions.
A useful way to compare different SPF levels is to look at how much UVB each filters:
| SPF | Approx. UVB filtered | Approx. UVB reaching skin |
|---|---|---|
| SPF15 | 93% | 6.7% |
| SPF30 | 97% | 3.3% |
| SPF50 | 98% | 2% |
SPF30 vs SPF50: how big is the difference?
The jump from 30 to 50 sounds substantial, but SPF numbers don't work like a simple percentage scale.
SPF30 filters around 97% of UVB radiation when correctly applied. SPF50 increases that to around 98%.
SPF30
Filters around 97% of UVB radiation, leaving approximately 3.3% reaching the skin under test conditions.
SPF50
Filters around 98% of UVB radiation, leaving approximately 2% reaching the skin under test conditions.
So SPF50 does provide more protection, but it isn't dramatically more protective than SPF30. Both already filter the vast majority of UVB radiation.
That's why choosing between them isn't simply a case of assuming the bigger number is always necessary. How much time you're spending outdoors, UV levels, your skin and how well you apply your sunscreen all matter too.
SPF30 already provides a high level of protection
SPF30 filters around 97% of UVB compared with around 98% for SPF50. SPF50 gives you additional protection, but both are high-protection sunscreens when correctly applied.
When is SPF30 enough?
SPF30 provides a high level of UVB protection when it's applied generously and correctly.
For many people, a good SPF30 is a practical choice for everyday sun protection, particularly if you like the texture and are therefore happy to apply it properly.
An SPF30 facial sunscreen can work particularly well as the final step of a morning skincare routine, providing daily protection without necessarily feeling like traditional beach sunscreen.
Under controlled conditions, SPF30 also means it takes considerably more UV exposure for protected skin to burn than it would without sunscreen. In the real world, though, the protection you actually receive depends on how much you apply, the strength of the sun and whether sunscreen is lost through swimming, sweating or towelling.
When should you choose SPF50?
SPF50 provides a little more UVB protection than SPF30 and can be particularly useful when your exposure is likely to be greater.
- You're spending a long time outdoors.
- UV levels are high.
- You're on holiday somewhere with stronger sunshine.
- You have very fair or particularly sun-sensitive skin.
- You're particularly concerned about sun-induced pigmentation or visible skin ageing.
- You simply prefer the additional protection of SPF50.
A higher SPF also means more UV exposure is required to produce sunburn under controlled conditions.
That doesn't mean SPF50 should be used as a reason to ignore reapplication or spend unlimited time in strong sunshine. Swimming, sweating, towelling and inadequate application can all reduce the protection you're actually getting.
SPF30 or SPF50? Both have their place.
A well-formulated SPF30 that's applied properly offers excellent everyday protection.
Choose SPF50 when you want the higher protection level, expect greater UV exposure or simply prefer the additional margin of protection.
SPF doesn't tell you everything: check UVA protection too
The SPF number primarily tells you about protection against UVB – the wavelengths most closely associated with sunburn.
But UVB is only part of the picture.
UVA penetrates more deeply into the skin and contributes to premature skin ageing, pigmentation and skin damage. Unlike UVB, its effects aren't necessarily accompanied by an obvious warning sign such as sunburn.
That's why a good sunscreen needs to provide protection against both UVA and UVB.
What does the UVA star rating mean?
In the UK, one familiar way to compare UVA protection is the UVA star rating.
The system runs from 0 to 5 stars and measures UVA protection in relation to the sunscreen's UVB protection. The more stars, the higher the relative level of UVA protection.
Look for a sunscreen with a strong UVA rating as well as an appropriate SPF. You'll commonly see 4 or 5-star UVA protection on high-protection sunscreens sold in the UK.
Not every sunscreen uses the UK star system. You may instead see the letters UVA inside a circle. On sunscreens sold under UK and European rules, this indicates that UVA protection reaches the required proportion of the labelled SPF.
Think UVA + UVB
SPF30 or SPF50 primarily tells you about UVB protection. Also look for good UVA protection, whether that's shown through a UK UVA star rating, the UVA circle or another recognised broad-spectrum standard.
Why mineral sunscreen is particularly interesting for UVA
This is one of the strengths of mineral sun protection.
Mineral sunscreens use filters such as zinc oxide and titanium dioxide, which can provide broad-spectrum protection across UVA and UVB wavelengths.
Zinc oxide is particularly useful because it provides protection across a broad range of both UVA and UVB. That makes it an excellent filter for formulating mineral sunscreens where broad-spectrum protection is important.
Titanium dioxide also provides UV protection, although its protection profile isn't identical to zinc oxide.
At MyPure, we favour non-nano mineral sun protection. If you'd like to understand how mineral SPF differs from conventional chemical sunscreen, read our guide to mineral vs chemical sunscreen.
Why how you apply sunscreen matters so much
The SPF printed on the bottle is based on sunscreen being applied at a specified amount during testing.
Apply significantly less and you won't receive the labelled level of protection.
That makes application every bit as important as whether the bottle says SPF30 or SPF50.
1. Apply generously
Use enough sunscreen to cover exposed skin evenly rather than trying to make a small amount stretch further.
2. Don't miss easy-to-forget areas
Ears, neck, hairline, décolleté and the backs of the hands are easily overlooked.
3. Reapply
Follow the instructions for your sunscreen and reapply particularly after swimming, sweating or towelling.
4. Use shade and clothing too
Sunscreen is most effective as part of a wider approach to sun protection that includes shade, suitable clothing and avoiding unnecessarily prolonged exposure to strong sunshine.
SPF30 or SPF50: two different approaches
The right sunscreen depends partly on where and how you're going to use it. Here are two useful mineral options from MÁDARA.
MÁDARA Plant Stem Cell Age-Defying Face Sunscreen SPF30
MÁDARA Plant Stem Cell Age-Defying Face Sunscreen SPF30 is a mineral facial sunscreen designed to provide UVA and UVB protection in a skincare-focused formula.
Why we like it: the lightweight, subtly tinted formula makes it particularly appealing as an everyday facial SPF. It's the sort of sunscreen that can comfortably become the final step in your normal morning skincare routine.
Explore MÁDARAMÁDARA SPF50 Plant Stem Cell Ultra-Shield Sunscreen
MÁDARA SPF50 Plant Stem Cell Ultra-Shield Sunscreen steps the protection up to SPF50 while retaining the skincare-focused approach of the range.
Why we like it: it's a mineral facial SPF for days when you want higher protection, while still feeling like part of a modern skincare routine.
Explore MÁDARAThink about how you'll use it
SPF30: excellent protection and a practical choice for everyday use when applied correctly.
SPF50: a little more UVB protection for higher exposure, particularly sun-sensitive skin or simply when you prefer the higher SPF.
Whichever you choose, good UVA protection and correct application matter just as much as the number on the bottle.
Find your SPF
Explore MyPure's range of sun protection, including SPF30 and high-protection SPF50 formulas for face and body.
Shop Sun ProtectionSPF30 vs SPF50 FAQs
Is SPF50 much better than SPF30?
SPF50 provides more UVB protection, but the difference is smaller than the numbers 30 and 50 might suggest. SPF30 filters around 97% of UVB radiation, while SPF50 filters around 98% when correctly applied. Both therefore provide a high level of UVB protection.
Does a higher SPF mean you can stay in the sun longer?
SPF is related to the amount of UV exposure required to cause sunburn. Under controlled conditions, SPF30 means protected skin requires around 30 times as much UV exposure to produce the same level of sunburn as unprotected skin. In real life, factors such as UV intensity, swimming, sweating, towelling and how much sunscreen you apply affect the protection you receive.
Is SPF30 enough for everyday use?
SPF30 provides a high level of UVB protection when applied generously and correctly and can be an excellent everyday choice. Your needs will also depend on UV levels, your skin and how much time you're spending outdoors.
Should I use SPF30 or SPF50 on my face?
Both can provide excellent facial sun protection. SPF30 can work very well for everyday use, while SPF50 provides a little more UVB protection and can be useful when UV exposure is greater or you want the additional margin of protection.
What does the UVA star rating mean?
The UK UVA star rating runs from 0 to 5 stars and indicates UVA protection relative to UVB protection. The higher the number of stars, the greater the relative UVA protection. You may also see UVA inside a circle on sunscreens as another recognised indication of UVA protection.
Are mineral sunscreens good for UVA protection?
Yes, mineral filters can provide excellent broad-spectrum protection. Zinc oxide is particularly useful because it protects across a broad range of UVA and UVB wavelengths.
Does SPF50 last longer than SPF30?
A higher SPF means more UV exposure is required to produce sunburn under controlled conditions, but it doesn't remove the need to reapply. Follow the instructions for your sunscreen and reapply after swimming, sweating or towelling.
Can you still tan with SPF50?
No sunscreen blocks 100% of UV radiation, so tanning can still occur while wearing SPF50. A tan is a response to UV exposure rather than a sign of healthy skin, so good sun protection should aim to minimise unnecessary UV exposure.
Is SPF50 better for mature skin?
Protecting skin from UV is particularly important if preventing further visible sun damage is a priority. SPF50 provides slightly higher UVB protection than SPF30, but good UVA protection, generous application and consistent use are also important.
The bottom line
SPF30 versus SPF50 isn't a question of good versus bad. Both provide high levels of UVB protection when they're applied properly.
SPF30 filters around 97% of UVB and can be an excellent everyday sunscreen. SPF50 increases that to around 98%, giving you some additional protection when you want it.
And remember that the SPF number isn't the whole story. Look for good UVA protection too. In the UK, the UVA star rating can help you compare products, while mineral filters – particularly zinc oxide – are naturally well suited to providing broad-spectrum UVA and UVB protection.
Apply your sunscreen generously, reapply when necessary and use shade and clothing when appropriate.
SPF30 or SPF50? Both offer excellent protection. Choose the one that best suits your skin, your day and the amount of sun exposure you're expecting.
Please note: This article provides general skincare and sun-protection information rather than medical advice. Always follow individual sunscreen instructions. No sunscreen provides 100% protection from UV radiation, so combine SPF with sensible measures such as seeking shade and wearing protective clothing. If you have a diagnosed skin condition or specific concerns about sun exposure, seek appropriate professional advice.