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Babies under 6 months get all their water from breast milk or formula and should not be given extra water. From 6 months, small sips with meals are fine; after that, daily needs rise with age and size.
Enter your child's age, sex and weight to see recommended drinks a day (water, milk and other drinks), total water including food, and the weight-based maintenance fluid used by doctors.
| Sex | Boy |
| Age | 60 months |
| Weight | 18 |
| Weight Unit | kg |
| Drinks a day (water, milk and other drinks) | 1.2 litres (5 cups of 240 ml) |
| Total water incl. food | 1.7 litres a day |
| Maintenance fluid by weight (Holliday–Segar) | 1,400 ml a day |
| Extra in hot weather or sport | + 250–500 ml per hour of activity |
1.2 litres (5 cups of 240 ml).
Try this example →| Sex | Boy |
| Age | 180 months |
| Weight | 55 |
| Weight Unit | kg |
| Drinks a day (water, milk and other drinks) | 2.6 litres (11 cups of 240 ml) |
| Total water incl. food | 3.3 litres a day |
| Maintenance fluid by weight (Holliday–Segar) | 2,200 ml a day |
| Extra in hot weather or sport | + 250–500 ml per hour of activity |
2.6 litres (11 cups of 240 ml).
Try this example →No. Under 6 months breast milk or formula provides all the water a baby needs, even in hot weather.
About 1.2 litres of drinks a day (around 5 cups), more in hot weather or sport.
Pale yellow urine, regular toilet trips and moist lips are good signs.