Understanding UPF Ratings

What “sun-safe clothing” really means, and why most babywear doesn’t make the cut.

As a parent, you naturally want to protect your baby’s delicate skin. But did you know that most everyday clothing, even long sleeves, doesn't provide adequate sun protection? Not to mention, sunscreen isn't recommended for babies under 6 months old, and even when you can apply it they suck, rub or cry it off.

Unless clothing is specifically tested and rated, it likely doesn’t block enough harmful UV rays to be considered truly sun-safe.

What is UPF?

UPF (Ultraviolet Protection Factor) is the official rating system used to measure how much UV radiation a fabric blocks. It’s similar to SPF, but for clothing instead of sunscreen. UPF 50+ is the highest rating available and means that the fabric blocks at least 98% of both UVA and UVB rays. For reference, a white cotton T-shirt often has a UPF of just 5 to 8, meaning 20% or more of UV rays still reach the skin.

What About Regular Baby Clothes?

The average baby bodysuit or T-shirt may look protective, but unless it’s made from densely woven or specially treated fabric, it likely offers little UV protection. Many typical cotton or jersey fabrics fall below UPF 15, especially when light-coloured or stretched. That’s why covering up doesn’t always mean your baby is sun safe.

Sun Baby Size Guide

GIRLS TOPS - ESSENTIAL SIZE GUIDE (cm)
Please note: Sun Baby tops are a loose fit

Size	Chest Width	Top Length
000	25	28
00	26	31
0	27	33
1	28	35

BOYS TOPS - ESSENTIAL SIZE GUIDE (cm)
Please note: Sun Baby tops are a loose fit

Size	Chest Width	Top Length
000	27	31
00	28	35
0	29	37
1	30	39

UNISEX ONESIE - ESSENTIAL SIZE GUIDE (cm)
Please note: Sun Baby onesies are a loose fit, you can size down if you're looking for something snug.

Size	Chest Width	Total Length
000	21	32
00	23	34
0	25	37.5
1	26	39

PANTS – ESSENTIAL SIZE GUIDE (cm)
Please note: Sun Baby pants are a snug fit, consider sizing up if your bub is in the higher percentile for weight.

Size	Waist Width	Pants Length
000	17	30
00	18	33
0	19	37
1	20	41

Australia’s UPF Standards (ARPANSA)

In Australia, the ARPANSA (Australian Radiation Protection and Nuclear Safety Agency) sets the standard for UPF testing.

To be officially classified as sun protective clothing, a garment must be:
✔ Independently tested to AS/NZS 4399:2020
✔ Rated UPF 15, 30, or 50+ (with 50+ being the gold standard)
✔ Clearly labelled with its UPF rating and protection category

At Sun Baby, we only use fabrics that have been independently lab-tested to meet UPF 50+ standards, and we never rely on chemical coatings to get there. Our protection is built into the fabric, naturally.

Why It Matters for Babies

Baby skin is thinner, more sensitive, and more vulnerable to UV damage than adult skin - and damage in early childhood increases the risk of skin cancer later in life. Sun safety starts young. Our UPF 50+ garments offer reliable, all-day protection for babies aged 0–18 months, without overheating or compromising on comfort.

UPF Protection Checklist

When choosing sun-safe clothing for your baby, look for:

✔ A visible UPF rating (not just “long sleeves”)
✔ Coverage for neck, hands, legs, and feet
✔ Breathable, natural fibres (like bamboo)
✔ A trusted brand that follows ARPANSA standards

Because not all “coverage” is created equal.