Water Intake Calculator
Estimate daily water needs based on body weight, climate, and activity level.
How it works
Rule of thumb: 30–40 mL per kg. Add 500–1000 mL per hour of vigorous exercise.
70 kg adult, moderately active → ~2.5–3 L/day.
Frequently asked questions
- Is 8 glasses a day a rule?
- It's a rough guide, not evidence-based. Individual needs vary.
- Does coffee count?
- Yes — the diuretic effect at normal intake is small.
- Can I drink too much?
- Rarely — extreme overconsumption can cause hyponatremia.
- What are signs of dehydration?
- Dark urine, headache, fatigue, thirst.
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