Independent buying guides for small-space baby gear

Diaper Size Calculator

Diaper sizes are based on weight, and ranges overlap between sizes. Enter your baby's weight and age for a size and a rough monthly count.

Result

Likely size
Size 1 (close to Size 2)
Weight
12 lb / 5.4 kg
Typical per day
8-10
Typical per month
240-300

Brands differ. Size up when you see leaks, red marks or tabs that barely close, even if the weight is still in range.

How this calculator works

Typical ranges: Preemie under 6 lb, Newborn up to 10 lb, Size 1 8-14 lb, Size 2 12-18 lb, Size 3 16-28 lb, Size 4 22-37 lb, Size 5 27-35+ lb, Size 6 35+ lb. Daily counts are common planning ranges that fall as babies get older.