For a newborn baby, you should typically buy (roughly 140–200 diapers) or 1 to 2 large boxes (around 250–300 diapers) to start. This supply is usually enough for the first 2 to 3 weeks.

: Most major retailers like Target, Walmart, or Costco allow you to exchange unopened boxes for a different size if your baby grows faster than anticipated.

: There is chafing or deep red lines around the baby's legs or waist.

Avoid overstocking newborn sizes because babies often outgrow them within , and some larger babies (over 9 lbs) may skip the newborn size entirely and go straight to Size 1. Key Diaper Math

: Don't buy in bulk for one brand until you know it fits your baby well and doesn't cause irritation or leaks. When to Size Up You'll know it's time to move to Size 1 if you notice:

: The diaper can no longer hold the volume of urine.

: You can expect to use approximately 280 to 360 diapers in the first month. Smart Stocking Tips

: You cannot comfortably fit two fingers under the waistband.