Water Intake Calculator
Water Intake Calculator
Calculate your recommended daily water intake based on body weight, activity level, and climate. Get results in mL, liters, ounces, and cups.
Why Hydration Matters
- Cognitive function — even mild dehydration (1–2%) impairs concentration and memory
- Physical performance — dehydration reduces endurance and strength
- Digestion — water aids nutrient absorption and prevents constipation
- Temperature regulation — sweating and respiration require adequate fluid intake
Daily Water Intake Guidelines
| Organization | Men | Women |
|---|
| US National Academies | 3.7 L (125 oz) | 2.7 L (91 oz) |
| WHO | ~2.5 L | ~2.2 L |
| European Food Safety Authority | 2.5 L | 2.0 L |
These are total water from all sources including food, which contributes roughly 20% of daily intake.