US kids clothing sizes run 2T, 3T, and 4T, then the numbers 4, 5, 6, 6X, 7, 8, 10, 12, 14, and 16 (often labeled XS to XL). The number starts near your child's age but is built around height and weight, so buy by measurement, because the same label is not the same size across brands.
Shopping a European label around US 10-12? See what size 140 means.
Key takeaways
- Kids sizes go 2T–4T, then 4, 5, 6, 6X, 7, 8, 10, 12, 14, 16; a matching XS–XL scale runs alongside.
- The size number starts near the child's age but maps to height and weight, so measure before you buy.
- A youth small is about a US size 6–8; a youth large is about a US size 14–16.
- European sizes are simply the child's height in centimeters (a US 5 is about EU 110).
- Labels drift by brand — in our 2026 Size Index the same label was not the same size, so trust the tape measure.
How do US kids clothing sizes work?
US kids sizes start where toddler sizes end. After 2T, 3T, and 4T, most brands switch to single numbers — 4, 5, 6, 6X, 7, 8, 10, 12, 14, 16 — and many add a matching XS to XL scale. The number begins near your child's age, but it is drawn from standard height and weight ranges, so fit follows the body, not the birthday. A 6X sits between a regular 6 and a 7, giving a little extra length and width for a child who has outgrown a 6 but is not ready for a 7. Around size 7, many brands split into separate boys' and girls' departments. For the step up from toddler clothes, see what size a 2-year-old wears.
What is the full kids and youth size chart by age and height?
Here is the full picture in one place. Ranges are approximate and overlap on purpose — pick the size whose height and weight range best matches your child, and size up when they fall between two.
| US kids size | Approx age | Height | Weight | XS–XL | EU (cm) |
|---|---|---|---|---|---|
| 2T | ~2 yr | 33–35 in (84–89 cm) | 28–30 lb | — | 86–92 |
| 3T | ~3 yr | 36–38.5 in (91–98 cm) | 31–34 lb | — | 92–98 |
| 4T / 4 | 4–5 yr | 39–42 in (99–107 cm) | 35–40 lb | XS | 104–110 |
| 5 | 5–6 yr | 42–45 in (107–114 cm) | 40–46 lb | XS | 110 |
| 6 | 6–7 yr | 45–47 in (114–120 cm) | 46–52 lb | S | 116–120 |
| 6X / 7 | 7 yr | 47–50 in (120–127 cm) | 52–58 lb | S | 122 |
| 8 | 8 yr | 50–53 in (127–135 cm) | 58–66 lb | M | 128–134 |
| 10 | 9–10 yr | 53–57 in (135–145 cm) | 66–76 lb | M | 140 |
| 12 | 11–12 yr | 57–61 in (145–155 cm) | 76–90 lb | L | 146–152 |
| 14 | 12–13 yr | 61–63 in (155–160 cm) | 90–105 lb | L | 158–164 |
| 16 | 14–16 yr | 63–65 in (160–165 cm) | 105–120 lb | XL | 170 |
Sizes are approximate general fit guidance, not medical or growth advice. Children grow at their own pace, so if you have questions about your child's growth or development, ask your pediatrician. See our medical disclaimer.
What size is a youth small?
A youth small (YS) maps to about a US kids size 6–8 in most brands — roughly ages 6 to 8, or about 46–50 inches (117–127 cm) tall. Youth letter sizes, used on team shirts, hoodies, and athletic wear, are a shorthand for the numeric sizes, and they run a little differently from everyday kids' clothing. Always check the brand's own height range before you order.
What size is a youth large?
A youth large (YL) maps to about a US kids size 14–16 — roughly ages 11 to 13, or about 55–60 inches (140–152 cm) tall. It is the second-biggest youth size, sitting just below youth XL (18–20). If your child is between a youth large and an adult small, compare chest and length measurements, because a youth large is usually cut narrower than an adult small.
What is a youth shirt size chart (XS to XL)?
Youth shirt sizes translate the numeric kids sizes into letters. Here is how the common youth apparel scale lines up, though brands vary by an inch or two either way. Note that these athletic youth sizes are cut a little smaller than the everyday numeric sizes in the chart above — a youth large runs shorter than a girls' or boys' size 14 — so match the brand's own height range before ordering.
| Youth size | US numeric | Approx age | Height |
|---|---|---|---|
| YXS | 4–5 | 4–5 yr | 40–43 in (102–109 cm) |
| YS (youth small) | 6–8 | 6–8 yr | 46–50 in (117–127 cm) |
| YM | 10–12 | 8–10 yr | 51–54 in (130–137 cm) |
| YL (youth large) | 14–16 | 11–13 yr | 55–60 in (140–152 cm) |
| YXL | 18–20 | 13–15 yr | 60–64 in (152–163 cm) |
Boys size chart vs girls size chart: what is the difference?
Through the toddler and little-kid years, boys' and girls' numeric sizes use the same numbers and nearly the same height and weight ranges. They diverge around size 7: girls' sizes often add a 6X and run slimmer through the waist and hip, while boys' sizes are cut straighter and a touch roomier at the same number. The age-to-height guide above works for both — the real difference is in the cut, not the number, which is another reason to size by measurement.
How do US kids sizes convert to EU sizes?
European sizes are the simplest system of all: the number is the child's height in centimeters. A US 5 is about EU 110, a US 8 is about EU 128, and a US 14 is about EU 158–164. Measure height in centimeters and match the nearest EU number. Our EU size conversion guide (50 to 140) lists every step from newborn to teen.
Why does the same size fit differently across brands?
Because the label is not a standard. In our 2026 Size Index we compared 30 US brands and found the same label was not the same garment: a “3-6M” top ranged from 14.5 to 20 lb, and “18-24M” ranged from about 26 to 32 lb. The same pattern shows up across kids and youth sizes, so two size-8 shirts from different brands can fit a child quite differently. The honest takeaway is to buy by measurement, not by the number on the tag.
How do I measure my child for the right size?
Stand your child against a wall to read height, then use a soft tape for the chest (around the fullest part), the waist (at the natural waistline), and the hip. Compare those numbers to the chart's ranges rather than to the age column, since age is only a starting point. When your child lands between two sizes, size up — kids grow into clothes faster than they grow out of them. Our free Size Finder turns a few measurements into a recommended size in seconds.
Sources: Babbez Baby Clothing Size Index 2026 (30 US brands); Babbez EU size conversion guide (50–140); ASTM standard body-measurement tables for children's apparel (D6192 / D6458); individual brand size charts, which vary — always check the label. This chart is general fit guidance and not medical advice; see our medical disclaimer.
