Infant sizes refer to the clothing and diaper measurements designed for babies, typically ranging from newborn to 24 months. These sizes are categorized by age, weight, and height, ensuring a proper fit for infants as they grow. Common size labels include newborn, 0-3 months, 3-6 months, 6-12 months, and 12-24 months. When shopping for infant clothing, it's essential to consider the brand, as sizing can vary. Additionally, some items may be labeled as preemie for premature babies. Parents should also account for growth spurts, which can affect how long a particular size will fit their child.