For a 3-month-old baby, feeding amounts and frequency depend on whether the baby is breastfed or formula-fed, but general guidelines are as follows: Breastfed Babies:

• Typically nurse every 2 to 3 hours during the day, with feedings about 8 to 12 times in 24 hours.
• Each feeding usually results in about 3 to 4 ounces consumed, though this can vary.
• Babies may start to have longer stretches between feedings overnight, sometimes up to 6 hours.
• Feeding on demand is recommended, following the baby's hunger cues.
• Around this age, babies may experience growth spurts and want to eat more frequently.
• Signs of adequate feeding include contentment after feeding, soft breasts, and healthy weight gain

Formula-Fed Babies:

• Usually feed every 3 hours during the day and every 3 to 8 hours overnight.
• Typical intake is about 4 to 6 ounces per feeding.
• Total daily intake generally ranges from 20 to 32 ounces.
• Most formula-fed babies eat about six to eight times per day.
• At 3 months, babies often consume about 5 ounces per feeding, six to eight times daily.
• Like breastfed babies, formula-fed infants may have growth spurts requiring more frequent or larger feedings

Additional Notes:

• The American Academy of Pediatrics recommends waiting until about 6 months before introducing solid foods; breast milk or formula remains the sole nutrition source at 3 months

• Monitoring diaper output (at least 4-5 wet diapers per day) is a good indicator of sufficient intake

• Feeding schedules may vary widely; following the baby's hunger cues is best.

In summary, a 3-month-old baby typically eats about 3 to 6 ounces per feeding, 6 to 12 times per day, with breastfed babies feeding more frequently but often consuming slightly less per feeding than formula-fed babies