Snowsuit Size Calculator
Enter your baby’s height and age to find the snowsuit or bunting size that fits now and leaves room for the layers underneath.
The right size keeps the warmth in
A snowsuit that is too tight compresses the layers underneath and loses their insulating air, while one that is far too big lets cold air circulate and leaves cuffs flopping over little hands. Aim for enough room to add a fleece without straining the zip, with cuffs that sit at the wrist and ankle.
Once the suit fits, use the Baby Layering Guide to decide what goes underneath, and the Winter Car-Seat Safety Checker before buckling a snowsuited baby into the car.
Frequently Asked Questions
Should I buy a snowsuit by age or by height?
By height. Age labels are only an average, and babies of the same age can differ by a whole size, so a snowsuit chosen by height fits far more reliably. This calculator maps your child's height in centimetres to the standard size band and uses their age only to flag a mismatch worth double-checking against the brand's own chart.
Should I size up a snowsuit for winter?
Often, yes. A snowsuit is worn over a jumper and sleeper, so it runs small once those layers are underneath, and a roomy suit is warmer and lasts more of the season than a tight one. When your child is near the top of a size band, this tool recommends going up to the next size for that layering room. The main trade-off is that cuffs and ankles shouldn't be so long they cover the hands and feet loosely.
How do I measure my baby's height for sizing?
Lay a young baby on their back on a flat surface, gently straighten the legs, and mark the surface at the top of the head and the bottom of the heel, then measure between the marks. A standing toddler can be measured against a wall with heels, bottom, and shoulders touching it. Measure without a bulky nappy or shoes for the truest figure, and re-check every couple of months in the fast-growing first year.
Is this an official sizing standard?
No. Baby-clothing sizes are not standardised, so brands vary — this calculator uses common height bands as a starting point, not an exact fit for any one label. Always check the specific manufacturer's size chart, and where you can, try the suit on over the layers your child will actually wear. This is a shopping aid, not medical or safety advice.
A shopping aid based on common height bands and the details you enter — sizes vary by brand, so always check the manufacturer’s chart. Not medical or safety advice.