What is SPF & how often should you apply it?

Sun protection is essential to help you maintain healthy-looking skin and prevent long-term damage. Spending too long in the sun can cause sunburn, premature ageing and increase the risk of skin damage. Sunscreen plays a crucial role in shielding your skin from harmful UV radiation, and SPF is a key factor when you’re choosing the right protection.

What is SPF?

What does
SPF stand for?

The SPF on sunscreen stands for sun protection factor, a relative measurement of how long the sunscreen will protect your skin from ultraviolet (UV) rays. The higher the SPF number, the higher the percentage of UVB rays it will block.

How does SPF work?

SPF is determined by measuring the time it takes for redness (erythema) to appear on unprotected skin exposed to a specific dose of UV rays, compared with unprotected skin. So, in theory, an SPF 30 sun cream would last 30 times longer than the same exposure without protection.

In practice, though, it's a different story, as how long a sun cream stays effective can depend on a number of factors, such as how much you apply, the UV index, and whether your skin is sweating or swimming. So the SPF value should be seen more as a guide, and you need to reapply it regularly.

SPF levels

The difference between
SPF levels

The difference between SPF levels lies in how much UVB protection they offer.

SPF 15 blocks approximately 93% of UVB rays
SPF 30 blocks about 97% of UVB rays
SPF 50 blocks approximately 98% of UVB rays

SPF is determined by measuring the time it takes for redness (erythema) to appear on unprotected skin exposed to a specific dose of UV rays, compared with unprotected skin. So, in theory, an SPF 30 sun cream would last 30 times longer than the same exposure without protection. In practice, though, it's a different story, as how long a sun cream stays effective can depend on a number of factors, such as how much you apply, the UV index, and whether your skin is sweating or swimming. So the SPF value should be seen more as a guide, and you need to reapply it regularly.

How to apply
SPF correctly

Applying sunscreen correctly is essential to make sure you get maximum UV protection. Even the most effective sunscreen won’t work if you don’t apply it properly.

1. Apply generously

You should apply sunscreen generously to all uncovered areas. The amount of SPF you need varies by age:

Under 3 years: Try to avoid exposing babies and young children to direct sun as far as possible by keeping them in the shade and using protective clothing, a hat, sunglasses and a parasol, as their skin is extremely delicate and more vulnerable to UV damage. For uncovered areas that might get indirect exposure, use a minimum of 5 to 10 ml for babies aged 6 months and over.
Children (3–5 years): At least 10–15 ml. For more info on choosing the right sun protection for children, have a look at NIVEA’s sunscreen guide for children.
Children (5–10 years): They need at least 15–20 ml for full coverage.
Adults and children over 10: Need at least 30–40 ml for the whole body.

Sunscreen for kids

2. Apply 15–30 minutes before sun exposure

This gives your sunscreen time to fully absorb and start protecting your skin.

3. Cover all exposed areas

Don’t forget areas like your ears, neck, scalp (if it’s exposed), and the backs of your hands and feet.

4. Use a dedicated face sunscreen

When you apply SPF to your face, make sure you use a sunscreen specially formulated for your face and sensitive skin.

How long does SPF 50 last and
how often should you reapply sunscreen?

The effectiveness of sunscreen decreases over time, especially with exposure to water, sweat or towel-drying. On top of that, the lower the SPF and the longer it’s been since you applied it, the fewer UVB rays will be filtered.

No matter which SPF level you use, to maintain optimal protection you should reapply sunscreen every two hours. If you’re swimming, sweating, or towel-drying, it will wear off more quickly, so you’ll need to reapply more often. Always check the sunscreen’s water-resistant label for specific guidance on reapplying during water activities. Regular reapplication helps you stay protected throughout the day.

Facts overview

What is SPF and
how often should you apply it

Application:
You should reapply sunscreen every two hours or more often if you’re swimming or sweating.

What is SPF:
SPF stands for sun protection factor, which shows how much protection your sunscreen gives you against UVB rays.

SPF levels:
SPF 15 blocks approximately 93% of UVB rays
SPF 30 blocks approximately 97% of UVB rays.
SPF 50 blocks approximately 98% of UVB rays.

Protection with SPF for face and body

Protection with SPF
for your face

Your face is highly exposed to UV rays, so putting on SPF every day is essential if you want to prevent sun damage and premature ageing. SPF 50 gives you higher protection, although lower SPFs can work during less intense exposure if you apply – and reapply – them correctly.

Apply sunscreen as the last step in your skincare routine and before you put on any makeup, and cover your face, neck and upper torso. Using moisturisers with SPF is a convenient way to build SPF into your routine.

Even though many makeup products now contain SPF, they’re usually not applied in big enough amounts to give you proper protection. So it’s still really important to use a sufficient amount of sunscreen for optimal protection.

For added convenience, the NIVEA 2in1 Prime UV Serum gives you instant SPF 50+ protection and smoothness in a lightweight, fragrance-free formula. Infused with Hyaluron to hydrate the upper layers of your skin and Licochalcone A to help support your skin’s natural defence mechanisms (in vitro tested), this serum helps combat sun-induced premature ageing while keeping your skin looking healthy. It absorbs quickly without feeling greasy, giving you seamless daily sun protection.

Designed for everyday ease, its premium dispenser makes application effortless. The 2-in-1 action protects and smooths, which makes it perfect for a busy lifestyle. It works well on its own or as a primer under makeup, delivering long-lasting hydration and defence so your skin looks healthy and feels soft.

Face sunscreens

Protection with SPF
for your body

Applying a high SPF properly helps make sure you get full-body UV protection and helps prevent sunburn and long-term skin damage. Adults need 30–40 ml of sunscreen for complete coverage, while children need 10–30 ml, depending on their age. Apply 15–30 minutes before sun exposure, covering your ears, neck, hands, feet and any other exposed areas. Reapply every two hours, especially when you’re exercising, to maintain effective protection.

NIVEA sun care product

Choosing the
right SPF for your skin

When you’re choosing a sunscreen, it’s important to pick an SPF level that suits your skin type, the environment and what you’ll be doing.

1
Fairer skin tones:
For fair skin tones, an SPF 50+ is recommended, as fair skin has lower melanin levels and is more likely to burn and experience skin damage.

2
Darker skin tones:
For darker skin tones, an SPF 30+ is usually sufficient, as melanin offers some natural UV defence. But this doesn’t remove the risk of sunburn, hyperpigmentation or skin damage, so daily SPF application is still essential. In some cases, an SPF 50 may be recommended, especially to protect your face if you’re dealing with high exposure or hyperpigmentation.

3
Oily skin:
For oily skin, it’s best to use a lightweight, mattifying sunscreen that won’t clog your pores or feel greasy. Sun protection products in fluid or gel form generally feel less oily than creams. Look out for products with an ultra-light texture and ingredients such as niacinamide, which can help absorb excess sebum and help prevent imperfections.

4
Sensitive skin:
For sensitive skin, choose sun creams that are specially formulated for this skin type and have been dermatologically tested. Fragrance-free, ethyl-alcohol-free and “for sensitive skin” options help reduce the chances of redness and discomfort.

5
Dry skin:
Dry skin benefits from hydrating sunscreens enriched with ingredients like hyaluronic acid, glycerine or ceramides to lock in moisture while still giving you UV protection. Many SPF-infused moisturisers offer both sun protection and hydration, helping to prevent dryness and flaking caused by long hours in the sun.

NIVEA Sun Protect & Moisture SPF 50 Lotion

Should you choose SPF 50 or 30?
What’s the difference?

Your choice between SPF 30 and 50 will mainly depend on your skin type, the UV index and how long you plan to stay in the sun. Although in theory SPF 50 blocks approximately 98% of UVB rays, compared to around 97% for SPF 30, the actual protection you get will depend on how much you apply, how long you’re exposed and how often you reapply.

Protection levels above SPF 50 only offer slightly more coverage, and no level of SPF can give you 100% protection. In most situations, SPF 30 is adequate protection if you apply it correctly and regularly; however, SPF 50 is still the safer option for fair skin or very intense exposure. If you’re looking for trusted sun protection, try our NIVEA Sun Protect & Moisture SPF 50 Lotion.

NIVEA SUN Protect & Moisture Lotion SPF 50+

NIVEA SUN Protect & Moisture Spray SPF 50+ provides broad-spectrum UVA and UVB protection, helping to prevent sunburn and premature ageing. Its formula contains vitamin E and vitamin C, with antioxidant properties, as well as Hyaluron, which can help your skin retain water. This spray protects your skin from harmful UV rays while keeping it moisturised for up to 48 hours*. Its formula absorbs quickly and leaves no white cast.

With a water-resistant formula, this sunscreen is ideal for outdoor activities (just remember to reapply it regularly, especially after swimming or sweating). It keeps your skin feeling soft, smooth and nourished while maintaining effective sun protection. Suitable for all skin types, its dermatologically tested formula gives you reliable care for everyday use.

^{*Instrumental evaluation, 35 women, 2022}

Summary

SPF shows you how effectively a sunscreen protects your skin from UVB rays. The higher the SPF, the more protection it offers – but reapplying every two hours is crucial if you want to stay safe in the sun. Apply sunscreen generously and evenly, and always reapply after swimming or sweating so your protection stays consistent.