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How many diapers will we need?
A free diaper calculator for year one: how many diapers your baby will use by size, and what they'll cost at the price you pay.
Box price ÷ diapers in the box. Store brands often cost less.
Diapers in year one
2,739
over 12 months
Total cost
$1,041
incl. $219 of wipes
Per month
$86.74
on average
By size
- Newbornup to about 10 lb (4.5 kg)304$91.20
- Size 1about 8 to 14 lb (4 to 6 kg)548$164
- Size 2about 12 to 18 lb (5 to 8 kg)699$210
- Size 3about 16 to 28 lb (7 to 13 kg)1,188$356
Registry tip: babies outgrow newborn diapers fast, and some skip them entirely. Buy one or two packs of newborn size and save the rest of your stash for Size 1 and Size 2. Switch sizes by weight and fit (leaks, red marks), not by age.
How many diapers does a newborn use per day?
Newborns use about 8 to 12 diapers a day in the first month, because they feed often and pee after most feeds. That falls to about 6 to 8 a day by the second half of the first year. Altogether, most babies go through roughly 2,500 to 3,000 diapers before their first birthday.
Diapers per day and size by month
Typical ranges. Your baby's size and your change habits move these up or down.
| Month | Typical size | Diapers a day | About per month |
|---|---|---|---|
| Month 1 | Newborn | 8 to 12 | 243 to 365 |
| Month 2 | Size 1 | 8 to 10 | 243 to 304 |
| Month 3 | Size 1 | 8 to 10 | 243 to 304 |
| Month 4 | Size 2 | 7 to 9 | 213 to 274 |
| Month 5 | Size 2 | 7 to 9 | 213 to 274 |
| Month 6 | Size 2 | 6 to 8 | 182 to 243 |
| Month 7 | Size 3 | 6 to 8 | 182 to 243 |
| Month 8 | Size 3 | 6 to 8 | 182 to 243 |
| Month 9 | Size 3 | 6 to 8 | 182 to 243 |
| Month 10 | Size 3 | 5 to 7 | 152 to 213 |
| Month 11 | Size 3 | 5 to 7 | 152 to 213 |
| Month 12 | Size 3 | 5 to 7 | 152 to 213 |
Weight ranges vary by brand. Typical: Newborn up to about 10 lb (4.5 kg), Size 1 about 8 to 14 lb (4 to 6 kg), Size 2 about 12 to 18 lb (5 to 8 kg), Size 3 about 16 to 28 lb (7 to 13 kg).
How we calculate this
Diapers = Σ (diapers per day for that month × 30.4 days), for each month from your baby's age to 12 months. "Typical" uses the middle of each range, "Fewer" the low end and "More" the high end. A typical year comes to about 2,700 diapers, inside the commonly quoted 2,500 to 3,000.
Cost = diapers × your price per diaper, plus wipes × price per wipe if you include them (we assume about 2 wipes per change). Sizes follow typical US brand weight charts. Every brand runs a little differently.
When to call your pediatrician
- Fewer wet diapers than expected for your baby's age (fewer than 6 a day after day 5).
- A diaper rash that's spreading, blistering or bleeding, or that hasn't improved after 2 to 3 days of care.
- Fewer wet diapers than expected for your baby's age (after day 5, fewer than 6 in 24 hours), or dark yellow urine.
- A temperature of 100.4°F (38°C) or higher in a baby under 3 months. Call right away, day or night.
- Very sleepy, floppy or hard to wake for feeds, or less alert than usual.
- Refusing feeds, or several feeds in a row that are much smaller than usual.
- Signs of dehydration: dry mouth, no tears, a sunken soft spot on the head, or no poop along with very few wet diapers.
- Yellow skin or eyes that's spreading or getting deeper, especially in the first week.
- Forceful or green vomiting, or blood in the poop.
Call 911 (or your local emergency number) if your baby has trouble breathing, turns blue or gray around the lips, or won't wake up.
If something feels off, trust your gut and call. That's what they're there for.
Frequently asked questions
How many diapers does a baby use in the first year?
Most babies use about 2,500 to 3,000 diapers in their first year. Cedars-Sinai puts it at about 6 to 10 a day, or 2,000 to 3,000 a year. Newborns use the most, often 10 or more a day, and the number drops as feeds space out.
How many newborn-size diapers should I buy?
Not too many. Many babies fit newborn size for only a few weeks, and bigger babies may skip it. One or two packs (about 60 to 150 diapers) is a good start. Stock up on Size 1 and Size 2 instead, which most babies wear for months.
How often should I change my baby's diaper?
Newborns usually need a change after most feeds and after every poop, which adds up to about 8 to 12 a day. As your baby gets older and pees less often but more at once, it drops to about 6 to 8. You don't need to wake a sleeping baby just to change a wet diaper.
Are cloth diapers cheaper?
Often, over time, but the costs are different. Cloth diapers need an upfront stash, covers and laundering, and they're changed more often because they hold less. The AAP notes that neither cloth nor disposable is a clear environmental winner, so choose what works for your family.
How do I count wet diapers to check feeding?
From about day 5, look for 6 or more heavy wet diapers in 24 hours. In the first days, expect about one wet diaper per day of life. Our wet diaper checker compares your count with day-by-day guidance and lists the signs to call your pediatrician about.
Sources
- Cedars-Sinai: Diapers and Diaper Rash(opens in a new tab)
- Nemours KidsHealth: Diapering Your Baby(opens in a new tab)
- American Academy of Pediatrics (HealthyChildren.org): Diapers: Disposable or Cloth?(opens in a new tab)
- NHS Start for Life: Breastfeeding: milk supply (wet and dirty nappies)(opens in a new tab)
Last reviewed: November 2026
Feedoo Baby shares general information, not medical advice. Every baby is different. If you're worried about feeding, weight gain, diapers or your baby's health, call your pediatrician, midwife or health visitor.
Count the diapers that matter
Feedoo Baby logs every pee and poo in two taps and shows daily diaper counts, so you know when you're low on wet diapers (or just low on diapers).
- Two-tap diaper logging: pee, poo or both
- Daily, weekly and monthly diaper counts in Stats
- A reminder when a diaper change is overdue
- Shared with everyone who changes diapers
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