A mother messaged me from a chemist's counter in Nagpur last April. Two kids' sunscreens in her hand, one SPF 50 PA+++ and one SPF 30 PA++++, and a shopkeeper telling her the second one was "stronger". Short answer: PA++++ is not a strength rating. It is a UVA grade, the highest band on the Japanese PA scale, and a product has to measure a Protection Grade of UVA (PPD) of 16 or more on human skin before it can print it. SPF and PA cover two different rays doing two different things. In Indian weather, the PA half is the one parents consistently under-read.
At a glance
- PA stands for Protection Grade of UVA. Each plus is a measured band from a human test, not label decoration.
- PA+ = PPD 2 to under 4 · PA++ = 4 to under 8 · PA+++ = 8 to under 16 · PA++++ = 16 and above.
- SPF is about UVB, the burning ray. PA is about UVA: deeper, linked to tanning and premature ageing, and it passes through ordinary window glass.
- UVA stays high across the Indian year. Monsoon cloud and a pleasant Delhi December dull the heat. They do not switch the UVA off.
- For school-and-playground life, a broad-spectrum sunscreen at PA+++ that your child lets you apply every day beats a PA++++ bottle used twice a month.
What does PA++++ actually mean on the label?
The PA system comes from the Japanese Cosmetic Industry Association. It rests on a human test called PPD, persistent pigment darkening. Volunteers take a measured dose of UVA on bare skin and on sunscreen-covered skin. The lab then compares how much more UVA the protected patch needed before it showed that steady, hours-later darkening. Tolerated sixteen times the dose? The PPD is 16, and the product earns its fourth plus.
So a plus is a ratio of dose tolerated, the same way SPF is. Not a percentage. Not a number of hours. And nothing at all to do with how thick or opaque the cream looks. A sheer, almost invisible fluid can carry PA++++. A heavy white paste can carry PA+.
| Label mark | Measured PPD | Plain reading |
|---|---|---|
| PA+ | 2 to under 4 | Some UVA defence. Thin for an Indian summer. |
| PA++ | 4 to under 8 | Moderate. Fine for indoors-mostly, light outdoor exposure. |
| PA+++ | 8 to under 16 | High. The realistic daily band for school, park, cycling. |
| PA++++ | 16 and above | Very high. Beach, pool and hill-station days. |
| No PA mark at all | Not stated | Look for "broad spectrum" plus a UVA-in-a-circle symbol, or keep looking. |
Why the scale stops at four pluses
PA++++ is an open-ended top band, and that trips up most parents. Everything from PPD 16 to PPD 30 collapses into the same four pluses. Two PA++++ products need not be equal, and the label will never tell you which one is higher. The fourth plus was added to the scale in 2013 because formulas had outgrown PA+++. Beyond that point, the extra margin matters far less than whether the bottle comes out again at lunch.
PA vs SPF: what each number is measuring
SPF is a UVB number, measured by how much longer protected skin takes to turn pink. UVB is the ray behind a sunburn after an afternoon of cricket, and it swings hard with season, time of day and altitude.
UVA is the longer wavelength. It reaches further into the skin. It is the one associated with tanning, and with pigmentation that settles in and takes months to fade. It also travels through glass, which is the part that changes what a parent buys. A high SPF with no UVA grading is half a sunscreen.
Labels say all of this differently depending on where they were written. Japan and much of Asia print PA pluses. The EU prints the letters UVA inside a circle, which means the UVA protection is at least one-third of the labelled SPF. The UK adds a star rating. India's testing rules are tightening as well, which is worth knowing before you judge any number on a bottle. We went through that in what the BIS in-vivo SPF rules change on kids' sunscreen labels.
How much UVA does an Indian child actually meet, season by season?
Here is where the pluses stop being trivia. Our seasons change how the sun feels far more than they change how much UVA arrives.
Summer: March to June
Both rays peak. The UV index in central India sits in the double digits through the middle of the day, and nobody argues about sunscreen in May. The real problem is sweat. In a 43°C Nagpur afternoon a thick cream migrates into the eyes, and by the second week your child is refusing it at the door. Lighter mineral textures, on twenty minutes before leaving, survive that better.
Monsoon: July to September
This is the season that catches almost everyone. Thick cloud scatters and soaks up a good share of UVB, so skin burns less and the day feels mild. UVA comes through thin and broken cloud much more freely. Meanwhile the children are outside in the first dry hour after a downpour, chasing a wet ball across a wet ground, with nothing on their faces. Humidity keeps a film of sweat on the skin and shortens how long any sunscreen stays put. Monsoon is a reapply-more season, not a skip-it one.
Winter: October to February
Kind sun, long outdoor hours. Sports day, 7am cricket, a Christmas-break hill station where thin air and reflective ground push UV back up. At our latitudes UVA varies far less across the year than UVB does, so the ray that pigments takes no winter holiday. Winter's second trap is dryness. On tight, flaky skin a sunscreen drags, the child scratches at it, and half of it is gone by assembly. Moisturise first, let it settle, then put the sunscreen over it.
Does your child really need PA++++?
Most Indian school children don't, and I say that as someone who makes sunscreen. Real life argues against the extra plus. A PA+++ product (PPD 8 to under 16), spread in a proper layer and topped up once at lunch, delivers far more actual UVA defence across a week than a PA++++ formula smeared thin on one cheek because it felt sticky.
Reach for PA++++ when exposure genuinely steps up. A Goa week. Long pool training. Snow or high-altitude travel. Or a child whose doctor has advised extra photoprotection for a specific reason.
Day to day, here is the order I would read a bottle in: a stated PA grade or UVA circle; zinc oxide or titanium dioxide if you want a mineral filter; a water-resistance figure in minutes if there is swimming or sweat; and a texture your child will not fight. That last one is why we settled our own Daily Defender Kids Mineral Sunscreen at SPF 40 PA+++ where we did. It is the band that still wears comfortably on a humid day, and the sunscreen a child accepts is the one that protects them.
Read any sunscreen label in 30 seconds
- Find two numbers, not one: an SPF and a PA grade (or a UVA-in-a-circle mark).
- Treat "broad spectrum" with no PA grade as a claim rather than a measurement.
- Scan the filter list. Zinc oxide and titanium dioxide mean mineral, and most children tolerate these best on the face.
- Check water resistance in minutes, usually 40 or 80, if there is a pool, a sports period or monsoon drizzle.
- Dab a little on the back of your hand. Sticky, strongly fragranced or heavily white-casting? It will be refused by day four.
- Check the expiry and the period-after-opening symbol. A bottle that has lived in a car boot through May has had a hard life.
Do this tonight
Three small changes, and none of them needs a new purchase.
- Move the bottle. Keep the sunscreen next to the school shoes instead of in the bathroom. Application failure is almost always a location problem.
- Fix the quantity. Two fingers' length of product covers a child's face and neck, and roughly one finger per arm. Most households use a third of that.
- Moisturise first in the dry months. Bath, moisturiser, two minutes to settle, then sunscreen. Over winter-tight skin the layer stays where you put it instead of balling up.
Then pick one reapply anchor. The lunch break, or the moment they climb out of the pool and towel off. One reliable top-up beats upgrading a plus.
When to see a doctor
Please have a paediatrician look at your child if you see sunburn with blistering, swelling, fever or unusual drowsiness; a rash that keeps appearing only on sun-exposed skin; a patch of skin that is changing in size, colour or texture and not settling; or any reaction after starting a new medicine, since some raise sun sensitivity. For a baby under six months, sun avoidance and clothing come first, and sunscreen is a conversation to have with your doctor rather than a default.
If you want one bottle a child will wear on a sticky monsoon morning and a dry January one alike, our Daily Defender mineral sunscreen was formulated for exactly that daily, unglamorous job.
In summary
- PA is a measured UVA grade: PA+ is PPD 2-4, PA++ is 4-8, PA+++ is 8-16 and PA++++ is 16 or above.
- SPF covers UVB and PA covers UVA, so look for both numbers — a high SPF alone leaves the UVA side unproven.
- UVA stays high through monsoon cloud and a mild Indian winter, and it passes through school-bus and car window glass.
- For everyday school and play, PA+++ applied in a proper layer and topped up at lunch beats PA++++ used thinly.
- Keep the bottle by the school shoes, use two fingers' length for face and neck, and reapply roughly every two hours outdoors.
Frequently asked questions
Is PA++++ better than PA+++ for my child?
On paper, yes — PA++++ means a measured PPD of 16 or above, while PA+++ sits between 8 and 16. In practice the gap closes fast, because UVA defence depends on how much product goes on and whether it is topped up. For daily school use, PA+++ applied generously and reapplied once usually protects better than PA++++ applied thinly. Save the fourth plus for beach, pool and hill-station days.
What is the difference between SPF and PA on a sunscreen label?
SPF measures protection against UVB, the ray that burns, and is tested by how much longer protected skin takes to redden. PA measures protection against UVA, the deeper ray linked to tanning and premature ageing, tested through persistent pigment darkening. They are independent numbers. A high SPF with no PA grade or UVA symbol leaves the UVA side unproven, so look for both.
Does my child need sunscreen during the Indian monsoon?
Yes. Cloud cover scatters and absorbs a fair share of UVB, so skin burns less and the day feels mild, but UVA passes through thin and broken cloud much more freely. Children also play outdoors in the gaps between showers. Humidity keeps sweat on the skin and shortens how long any layer stays put, so monsoon is a reapply-more season rather than a skip-it one.
Does UVA really come through window glass?
Ordinary window glass blocks most UVB but lets a good share of longer-wavelength UVA through. That matters for a child who sits by a school-bus or car window every day, because there is no heat or glare to warn you. It is one practical reason to choose a daily sunscreen with a stated PA grade rather than only an SPF number.
Why do some sunscreens show a UVA in a circle instead of PA pluses?
They follow the European convention. The UVA-in-a-circle mark means the product's UVA protection is at least one-third of its labelled SPF. The UK adds a star rating, and Japan and much of Asia use the PA plus scale. All three are describing the same thing in different dialects, so any one of them is a reasonable sign the UVA side has been measured.
Is PA++++ safe for a toddler's skin?
A PA grade says nothing about gentleness — it is purely a measure of UVA protection, and a high grade can come from mineral or synthetic filters alike. Judge suitability by the filter list, the fragrance, the texture and a patch test on the inner forearm. Mineral filters such as zinc oxide and titanium dioxide are the usual starting point for young, sensitive skin, and for babies under six months ask your paediatrician first.
