A baby size guide for through the zeros

Viva Bianca

Viva Bianca

Viva is a writer, editor and mum (AKA professional snack bitch) – and not in that order. With a background in film, feminism and culture journalism, Viva brings her curiosity for storytelling to her role as Culture & Lifestyle Editor at Kiindred, and loves offering advice and tit-bits to other parents - it takes a village!
Updated on Jul 02, 2024 · 6 mins read
A baby size guide for through the zeros

Wardrobe shopping for someone you haven’t even met and whose birth size is yet to be determined can prove challenging. But in today's information-overloaded reality, this precious little mystery, waiting to reveal itself, can also be quite fun… Needless to say, if you’ve never shopped for baby clothing before, you’re probably quite confused about all the zeros!

We’re here to help you understand the science behind baby sizing – and to give you the heads up about when to drop a zero!

Bear in mind that, like us, every baby will grow at slightly different stages and ages, so there’s no exact one-size-fits-all blueprint for babies and clothing sizes. Babies come in various shapes and sizes, and understanding this variability is crucial for choosing the right clothing sizes. As babies grow at different rates, it’s important to consider factors like age, weight, and length when choosing clothing.

Baby clothes size chart

Navigating the world of baby clothes can be overwhelming, especially with the varying sizes across different brands. To ensure a proper fit for your baby, it’s essential to use a baby clothes size chart. Detailed American and European baby clothing size charts provide estimated weight and height ranges for each size, helping you understand how different baby clothing brands will fit your child. It also means that you can make avoid the hassle of returns or exchanges (and that’s always a win).

Size 00000

Yes, that’s a lot of 0’s! Size 00000 is for premature babies (about 2kg). Although you can’t normally know in advance if your baby will be born preemie, if you’re anticipating your baby’s grand earthside entrance at around 40 weeks (or a little over or under), you probably don’t need to buy this size. The next size up is typically for a newborn baby. However, keep in mind the variability in newborn size. Some babies may quickly outgrow the standard newborn size, so considering the difference between newborn and 0-3 months sizes is important. Always consider your baby’s weight and height when choosing clothing sizes.

Hint: It’s tiny! If your baby does surprise you with an earlier-than-expected arrival, you can always ask a family member or close friend to dash to H&M to pick up some 00000’s onesies and drop them off at the hospital.

                                                                                                                                                                    Size 0000

This size is for newborns (around 3kg) and is the most common clothing size for the first month or so of a baby’s life. Most baby clothing sizes are based on the average age, weight, and length of children at certain ages. Definitely invest in some staple baby pieces (onesies, singlets, bodysuits, socks, pants/leggings, newborn clothes) in size 0000, but remember, your baby will outgrow this size quicker than any other clothing size in their future wardrobe.

Also, be mindful that some babies are born much bigger than expected, so if your baby is born weighing around 4kg, they may well miss size 0000 altogether. Our advice is to not go overboard with your size 0000 collection. You may only get a few weeks (or none) out of them!

Size 000

Size 000 is a common category in baby clothes sizes, designed for babies aged 0-3 months old (or around 6kg). You’ll probably get more mileage out of this size than size 0000, so feel free to buy more of each piece (onesies, singlets, bodysuits, socks, pants/leggings) in this size. Don’t worry if your baby is swimming in their size 000 onesie to begin with; you can always roll up sleeves and waistbands. Your little one will grow into this size before you know it!

When considering baby sizes, it’s important to note the differences between sizes, such as 24 months and 2T. While 24 months is geared toward babies still in diapers with more babyish styles, 2T offers more mature toddler styles. Always consider your baby’s measurements and weight to ensure a comfortable fit.

Size 00

Size 00 is for babies aged 3-6 months (or 4-7 months) and will be the first range of clothing your baby will likely make a big mess of! That’s because it’s about the age they will be introduced to solids – and possibly even start exploring the house. So, by the time your baby has reached size 00, you might want to consider investing in some ‘play clothes’, which have the added benefit of expanding your baby’s wardrobe from onesies and bodysuits to overalls, tops and pants.

For summer babies, consider lightweight hats and swimsuits that provide sun protection and keep them cool.

When shopping for baby clothes in size 00, it’s important to understand how different brands size and label their garments.

Size 0

Size 0 is for a 9-month-old (roughly), so, because you can expect a lot of activity at this age from your little one (crawling, climbing, cruising, maybe walking, playing, eating), it would be a good idea to be prepared for numerous outfit changes a day. Investing in several pairs of pants, tops, singlets, onesies and extra play clothes for this stage would be wise. Baby clothing sizes explained in detail can help parents choose the right size for their active baby.

For winter babies, it is essential to have a snowsuit or bunting to keep them warm in colder weather.

Tip: Choose clothes that won’t inhibit your baby’s will to explore – and the ability to learn to crawl and walk. Soft, stretchy organic cotton is ideal.

Size 1

What a milestone! You’ve spent an entire year with your bundle of joy, enveloping them with love, nurture, nutrition and guidance (and with all the sleepless nights, you’ve likely also aged about 5 years!). This is a fun age to shop for because if your baby hasn’t begun walking yet, they will probably begin to test the waters pretty soon.

That means it’s time for shoes and to start having a little fun with fashion – think skirts, dresses, chinos or overalls to enter the playing field. Oh to be a baby fashionista! Shopping for a baby girl or boy at this stage is especially enjoyable as you explore different types of clothing items.

Bonus tips for baby clothing sizes

  • uy gender-neutral/unisex clothing, where possible. If you’re planning on having more than one baby, your future self will be grateful.
  • Choose zips or press studs over buttons. Buttons are a nighttime nappy change headache!
  • Consider buying singlet suits like bodysuits because they don’t ride up a baby’s body.
  • Envelope shoulder tops and bodysuits enable you to pull the garment down the baby’s body to remove it, to avoid pulling any nappy leakages over your baby’s head. Trust us, accidents will happen!
  • Plan how many baby clothes to buy in each size. Consider the baby’s measurements, seasonal needs, and laundry schedule. Building the baby’s wardrobe in manageable increments ensures a safe and comfortable fit.

While there’s no exact one-size-fits-all blueprint for babies and clothing sizes, it’s a good idea to familiarise yourself with baby sizing and its accompanying ages/stages. That way, you can shop with a little more street smarts 😉.

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