How much water should a child drink?
A simple by-weight estimate to start with, plus the everyday signals that matter more than any number.
Kids don't need a complicated hydration plan. A weight-based estimate gives you a sensible daily target, and then their thirst and energy fill in the rest.
The short answer: this calculator uses the Holliday-Segar maintenance method to turn your child's weight into a daily fluid amount. Move it up on hot days and when they're active, and remember that food counts too.
Estimate your child's daily fluid
Children's Water Intake
A simple daily fluid estimate for kids, by weight.
Think of the number as a friendly starting point, not a strict quota. Active play, sports, and hot weather all raise the amount a child needs, sometimes by a lot.
The simplest everyday check is still the best one: a child who isn't thirsty and has pale, straw-colored urine is generally well hydrated.
Common questions
How much water should a child drink a day?
A common starting estimate uses the child’s weight: this calculator applies the Holliday-Segar maintenance method to give a daily fluid amount in cups, liters, and ounces. It’s a starting point, and children need more when they’re active or in the heat.
Does food count toward a child’s fluid?
Yes. The estimate covers total daily fluid from drinks and food, and water-rich foods like fruit, vegetables, soup, and yogurt all contribute. Plain water is still the best everyday default for drinks.
How can I tell if my child is drinking enough?
Day to day, thirst and pale-yellow urine are good signals. Dark urine, dry mouth, or unusual tiredness can mean they need more, and needs rise with activity, hot weather, and illness.
This is general education, not medical advice. Some conditions change a child's fluid needs, so check with your pediatrician if that applies.