Average Weight & Height for an 18-Month-Old (1.5 Years)

Growth at 18 Months

At 18 months, toddlers are growing at a slower but steady pace compared to infancy. The average 18-month-old boy weighs about 11.8 kg (26 lb) and measures about 82.4 cm (32.4 in). Girls average about 11.1 kg (24.4 lb) and 80.8 cm (31.8 in).

Toddler Eating Patterns

Eighteen-month-olds can be notoriously picky eaters. Their appetite naturally decreases as growth slows, and they may go through phases of eating only a few foods. This is developmentally normal. Offer a variety of foods, let your toddler decide how much to eat, and avoid food battles. Growth continues normally even through picky periods.

Walking, Running, and Beyond

Most 18-month-olds are walking confidently and beginning to run (with a stiff, toddling gait). They may be able to kick a ball, climb stairs with help, and stack blocks. Physical activity helps develop muscles and bones that support healthy growth. See our milestone tracker for the full picture.

The 18-Month Checkup

The 18-month well-child visit includes growth measurements, developmental screening, and often blood work (for iron and lead). Your pediatrician will plot your child's growth and check that they're following their curve. Use our growth dashboard to calculate percentiles before your appointment.