The growth-spurt size guide: when kids jump sizes
Sizes in Australia can be confusing, and kids never stay in one for long. Here's how to stay a step ahead.
How Australian sizes work
Australian baby sizes are age-based and start with the zeros. As a rough guide: 0000 is newborn, 000 is around 0 to 3 months, 00 about 3 to 6 months, and 0roughly 6 to 12 months. After that, sizes follow age: 1 for one-year-olds, 2 for two-year-olds, and so on. They're a starting point, not a rule, because babies vary enormously.
When the jumps happen
The fastest changes are in the first year, when a baby can move through three or four sizes. That's why the earliest clothes are so often barely worn. After the first birthday, sizes last longer, but expect steady growth spurts, especially heading into a new season.
Fit tips: go by your child's height and build more than the number on the label, check the waist and the length, and remember brands run differently. When buying pre-loved, ask the seller for measurements if you're unsure.
Shopping ahead without over-buying
- Buy the next size, not five sizes. Have the next size ready, but don't stockpile years ahead; tastes and seasons change.
- Match the size to the season. A size 1 winter coat is no use if your child hits size 1 in summer.
- Pre-loved makes it low-risk. Because it's cheaper, buying a size ahead costs little, and you can resell if the fit or season misses.
Sell the size they've left
Every growth spurt frees up a whole size of barely-worn clothes. Sell your baby gear as you go, and the money helps fund the next size up.
A note on sizing
The size ranges above are general Australian guidance. Every brand and every baby is different, so treat labels as a starting point and always check measurements for the best fit.
Related reading
Stay a size ahead
Pick up the next size pre-loved, and sell on the one they've outgrown.
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