Calculate your personalised daily water intake from weight, activity level, and climate. Get targets in litres, ml, and glasses per day. Evidence-based formula.
More free utilities you might find useful
Quick answers to common questions
The National Academy of Medicine recommends 3.7 litres for men and 2.7 litres for women from all sources. Practical formula: 35ml per kg of body weight. Add 500ml for every 30 minutes of vigorous exercise.
Yes. Overhydration (hyponatremia) dilutes blood sodium. Risk is real for endurance athletes drinking large volumes without electrolytes. Use thirst as your primary guide and pale yellow urine as a secondary indicator.
Yes. Despite caffeine's mild diuretic effect, caffeinated beverages contribute net fluid to hydration. The British Dietetic Association confirms tea, coffee, juice, and milk all count. Alcohol is the exception.
Processing runs in your browser. Your inputs are not sent to our servers.
Daily Target
3.1L
3150 ml
Glasses (250ml)
13
glasses of water
Base (35ml/kg)
2.5L
without exercise
Formula: 35ml × body weight + exercise + climate adjustments. Use thirst as your primary guide.