Water Intake Calculator
Water needs vary with body size, activity, climate and health. This gives a rough daily estimate and explains total water versus the water you drink.
Your result
Fill in the form and choose Calculate.
Estimates are educational. They do not diagnose any condition and do not establish eligibility for any medication. A licensed provider decides what is appropriate for you. Explore programs.
How it works
Total water (L) = 0.035 × kg + activity addition + climate addition. Activity adds 0 to 1.4 L; climate adds 0 to 1.0 L. About 80 percent of total water usually comes from drinks and 20 percent from food. The National Academies' adequate intake is about 2.7 L a day for women and 3.7 L for men.
Limitations
- If you have been told to limit fluids (for example with heart or kidney disease), follow your care team, not this estimate.
- Pregnancy and breastfeeding raise needs.
Does coffee count?
Yes. Caffeinated drinks contribute to total water intake.
Why might I need to think about water on a GLP-1?
Eating less means less water from food, thirst can be quieter, and vomiting or diarrhea increase losses.