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What diaper size does your baby need?
The right diaper size depends on your baby's weight, not their age. Enter the weight, or check the chart below.
Diaper sizes by weight
| Size | Weight |
|---|---|
| Size N | up to 10 lb (4.5 kg) |
| Size 1 | 10–14 lb (4.5–6.4 kg) |
| Size 2 | 14–18 lb (6.4–8.2 kg) |
| Size 3 | 18–28 lb (8.2–12.7 kg) |
| Size 4 | 28–37 lb (12.7–16.8 kg) |
| Size 5 | 37–44 lb (16.8–20 kg) |
| Size 6 | over 44 lb (20 kg) |
Does the diaper still fit?
- Red marks on the tummy or legs? The diaper is too small — go up a size.
- Leaking around the legs usually means the fit is too loose; leaking at the top usually means the diaper is too small.
- The tabs should fasten roughly at the middle of the tummy.
- Sizes overlap on purpose. On the boundary: the bigger size absorbs more (good for nights), the smaller one fits more snugly.
- Every brand uses slightly different weight ranges — the chart above is an average guide; the pack itself is leading.
Want this matched to your own baby?
Enter a birth date once and see what matters this week — free, no account needed.
Create your own overview →Also handy: how much formula does your baby need?
Guidance by age: 0–6 weeks · 6–12 weeks · 3–4 months · 4–6 months · 6–9 months · 9–12 months · 12–18 months · 18–24 months · 2–3 years · 3–4 years · 4–5 years