How our family sizing works
Each set fits one person. To match the whole family, add one set per family member — same design, each person's size — then check out together. Baby, kids', and adult sizes of the same design are made to match.
On this page: what each size label means, general body-measurement references, and how to measure. These are general references, not exact garment measurements — our supplier doesn't publish per-garment specs. If you're between sizes, we recommend sizing up.
Baby sizes (pajamas & rompers)
Our baby sizes are the baby's age in months. The romper style is a one-piece with snap buttons, made for babies on the move.
| Size | Typical age | Typical height | Typical weight |
|---|---|---|---|
| BABY 3to6M | 3–6 months | 24–26.5 in (61–67 cm) | 12–17 lb (5.5–7.7 kg) |
| BABY 6to9M | 6–9 months | 26.5–28.5 in (67–72 cm) | 17–20 lb (7.7–9 kg) |
| BABY 9to12M | 9–12 months | 28.5–30.5 in (72–77 cm) | 20–23 lb (9–10.5 kg) |
| BABY 12to18M | 12–18 months | 30.5–32.5 in (77–83 cm) | 23–27 lb (10.5–12 kg) |
| BABY 18to24M | 18–24 months | 32.5–34 in (83–86 cm) | 27–30 lb (12–13.5 kg) |
Kids' sizes
Age-based (pajamas: KIDS 2Y – 8to9Y)
Match the size to the child's age. If they're tall for their age, size up.
| Size | Typical age | Typical height |
|---|---|---|
| KIDS 2Y | 2 years | 33–35 in (84–89 cm) |
| KIDS 3to4Y | 3–4 years | 37–41 in (94–104 cm) |
| KIDS 4to5Y | 4–5 years | 41–44 in (104–112 cm) |
| KIDS 6to7Y | 6–7 years | 46–50 in (117–127 cm) |
| KIDS 8to9Y | 8–9 years | 50–54 in (127–137 cm) |
Height-based (crown tees, holiday sweater, skirt set)
Sizes like 66cm, 80cm, 100cm… are the child's height in centimeters — measure the child standing straight, and pick the closest size at or just above their height.
| Size (height) | Typical age | Typical weight |
|---|---|---|
| 66cm | 3–6 months | 13–17 lb (6–8 kg) |
| 72–73cm | 6–12 months | 17–22 lb (8–10 kg) |
| 80cm | 12–18 months | 22–26 lb (10–12 kg) |
| 90cm | 2 years | 28–31 lb (12.5–14 kg) |
| 100cm | 3–4 years | 31–37 lb (14–17 kg) |
| 110cm | 4–5 years | 37–44 lb (17–20 kg) |
| 120cm | 6–7 years | 44–55 lb (20–25 kg) |
| 130cm | 8 years | 55–64 lb (25–29 kg) |
| 140cm | 9–10 years | 64–77 lb (29–35 kg) |
| 150cm | 11–12 years | 77–95 lb (35–43 kg) |
| 160cm | 13–14 years | 95–115 lb (43–52 kg) |
Adult sizes
Men (pajamas: MEN M – XXL)
| Size | Chest (general reference) | Waist (general reference) |
|---|---|---|
| MEN M | 38–40 in (97–102 cm) | 32–34 in (81–86 cm) |
| MEN L | 42–44 in (107–112 cm) | 36–38 in (91–97 cm) |
| MEN XL | 46–48 in (117–122 cm) | 40–42 in (102–107 cm) |
| MEN XXL | 50–52 in (127–132 cm) | 44–46 in (112–117 cm) |
Women (pajamas: WOMEN S – XL)
| Size | Bust (general reference) | Waist (general reference) |
|---|---|---|
| WOMEN S | 34–35 in (86–89 cm) | 26–27 in (66–69 cm) |
| WOMEN M | 36–37 in (91–94 cm) | 28–29 in (71–74 cm) |
| WOMEN L | 38–40 in (97–102 cm) | 30–32 in (76–81 cm) |
| WOMEN XL | 42–44 in (107–112 cm) | 34–36 in (86–91 cm) |
Unisex tees (S – 3XL) & crown family sets
Our short-sleeve tees use standard unisex alpha sizes. The crown family sets use King (dad), Queen (mom), Prince (boy), Princess (girl) — pick each person's usual size within their role:
| Size | Chest (general reference) |
|---|---|
| S | 34–36 in (86–91 cm) |
| M | 38–40 in (97–102 cm) |
| L | 42–44 in (107–112 cm) |
| XL | 46–48 in (117–122 cm) |
| 2XL | 50–52 in (127–132 cm) |
| 3XL | 54–56 in (137–142 cm) |
Prince/Princess kids' sizes like Prince80 – Prince140 follow the height chart above (80 = 80cm tall, and so on).
How to measure
- Height (kids): stand the child barefoot against a wall, mark the top of their head, measure floor to mark.
- Chest/bust: tape around the fullest part of the chest, under the arms, keeping the tape level.
- Waist: tape around the natural waistline (the narrowest point), relaxed — not sucked in.
- When in doubt, size up — especially for pajamas and holiday wear, where a cozy fit beats a snug one.
Still unsure?
Email us at support@littlematchingshop.com with the product name and the heights of everyone you're matching — we'll help you pick. And remember: free US shipping on orders $75+ and 30-day returns, so you're covered either way.