Kids & Baby Clothing
Clothing Sizes · 6 specs
Direct Answer
Children's clothing sizes standardize growth stages from Preemie and Infant (0–24M) to Toddler (2T–5T) and Youth (Sizes 4–16), establishing height in centimeters/inches and weight in pounds/kilograms as primary fit metrics over calendar age.
Source: ASTM D4910 / ASTM D6554 / ISO 3635 (Children's Apparel) · Last reviewed Aug 28, 2026
Specs
| Governing Standards | ASTM D4910 (Baby) / ASTM D6554 (Toddler/Youth) / ISO 3635 |
| Baby / Infant Stage | Preemie, Newborn, 0-3M, 3-6M, 6-9M, 9-12M, 12-18M, 18-24M |
| Toddler Stage (T) | 2T, 3T, 4T, 5T (engineered with extra room for diapers/training pants) |
| Youth / Kids Stage | Sizes 4, 5, 6, 7, 8, 10, 12, 14, 16 (Alpha XS to XL) |
| European System (EU) | Sized directly by child height in cm (e.g., EU 104 = 104 cm tall child / ~4 years) |
| Primary Fitting Metric | Always use Height and Weight rather than age for optimal fit |
1. Baby & Infant Clothing Sizing (0–24 Months)
| Size Label | EU Size (Height cm) | Height (Inches) | Height (cm) | Weight (lbs) | Weight (kg) |
|---|---|---|---|---|---|
| Preemie (P) | EU 44 | Up to 17" | Up to 43 cm | Up to 5 lbs | Up to 2.3 kg |
| Newborn (NB) | EU 50 | Up to 21.5" | Up to 55 cm | 5–8 lbs | 2.3–3.6 kg |
| 0–3 Months | EU 56–62 | 21.5"–24.0" | 55–61 cm | 8–12.5 lbs | 3.6–5.7 kg |
| 3–6 Months | EU 62–68 | 24.0"–26.5" | 61–67 cm | 12.5–16.5 lbs | 5.7–7.5 kg |
| 6–9 Months | EU 68–74 | 26.5"–28.5" | 67–72 cm | 16.5–20.5 lbs | 7.5–9.3 kg |
| 9–12 Months | EU 74–80 | 28.5"–30.5" | 72–78 cm | 20.5–24.5 lbs | 9.3–11.1 kg |
| 12–18 Months | EU 80–86 | 30.5"–32.5" | 78–83 cm | 24.5–27.5 lbs | 11.1–12.5 kg |
| 18–24 Months | EU 86–92 | 32.5"–34.5" | 83–88 cm | 27.5–30.0 lbs | 12.5–13.6 kg |
2. Toddler (2T–5T) and Youth Sizing (4–16)
Toddler Sizing (2T–5T)
| Size Label | Height (Inches) | Height (cm) | Weight (lbs) | Weight (kg) | Chest (Inches) |
|---|---|---|---|---|---|
| 2T | 33"–36" | 84–91 cm | 24–30 lbs | 11–14 kg | 20"–21" |
| 3T | 36"–39" | 91–99 cm | 30–35 lbs | 14–16 kg | 21"–22" |
| 4T | 39"–42" | 99–107 cm | 35–41 lbs | 16–19 kg | 22"–23" |
| 5T | 42"–45" | 107–114 cm | 41–46 lbs | 19–21 kg | 23"–24" |
Kids & Youth Sizing (4–16)
| Size | Alpha | Height (Inches) | Height (cm) | Weight (lbs) | Chest (Inches) | Waist (Inches) |
|---|---|---|---|---|---|---|
| 4 / 5 | XS | 40"–45" | 102–114 cm | 35–45 lbs | 22"–23" | 21"–22" |
| 6 / 7 | S | 45"–50" | 114–127 cm | 45–60 lbs | 24"–26" | 22"–23" |
| 8 / 10 | M | 50"–56" | 127–142 cm | 60–85 lbs | 27"–28" | 24"–25" |
| 12 / 14 | L | 56"–61" | 142–155 cm | 85–110 lbs | 29"–31" | 26"–27" |
| 16 | XL | 61"–65" | 155–165 cm | 110–125 lbs | 32"–34" | 28"–29" |