Kids Clothing Size Calculator by Age & Height
This kids clothing size calculator works backwards from age and height — the numbers parents actually know — to give you the right size across infants, toddlers, big kids, and tweens. Enter age and height (or weight if you have it) and the tool returns sizes in US, UK, EU (cm), and JP for ages 0M to 14 years. Use the calculator below to get your exact fit in 30 seconds.
How it works
Measure yourself
Take your bust, waist, and hips with a soft tape. See the full measurement guide.
Enter the numbers
Type your measurements into the calculator above. Pick inches or cm — the tool converts both ways.
Get your size
Match the result against the brand's chart and order with confidence.
Kids' clothing — age vs height
| Age | US Size | Height | EU (cm) |
|---|---|---|---|
| 0–3M | 0–3M | 21–24" | 56 |
| 6–9M | 6–9M | 26–28" | 68 |
| 12M | 12M | 28–30" | 74 |
| 2T | 2T | 33–36" | 86 |
| 4 | 4 | 39–42" | 104 |
| 6 | 6 | 45–48" | 116 |
| 8 | 8 | 50–52" | 128 |
| 10 | 10 | 52–55" | 140 |
| 12 | 12 | 55–58" | 152 |
Frequently Asked Questions
Should I size by my child's age or height?
Height. Age is a guideline; kids vary 6+ inches at the same age. Match the height range on the brand's chart for a real fit.
How is 4T different from size 4?
4T is cut for diapers and post-diaper bodies, with snap closures and easy-on shoulders. Size 4 is cut for fully potty-trained kids.
Should I size up for kids' clothes?
Yes, by 1 — kids grow into clothes faster than out of them. Exception: special-occasion outfits and safety items (helmets, car seats), which need exact fit.
How does EU kids' sizing work?
EU labels are the height in cm. EU 122 means 122 cm tall, not age 12. If your child is 122 cm, order EU 122.
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