How much water should I drink per day?
The general guideline is about 35 ml per kg of body weight. For a 70 kg adult, that's roughly 2.5 liters (about 10 glasses) per day, adjusted for activity and climate.
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Free Water Intake Calculator | 1ClickTools
Calculate your recommended daily water intake based on your weight, age, activity level, and climate. Get results in liters, fl oz, cups, and glasses.
Frequently Asked Questions
Does coffee or tea count toward water intake?
Yes, caffeinated drinks contribute to hydration, though slightly less efficiently than plain water. Water, herbal tea, and other non-alcoholic beverages all count.
Should I drink more water when exercising?
Yes. You lose water through sweat during exercise. Add 350–1200 ml depending on intensity. Drink before, during, and after workouts.
How do I know if I'm drinking enough water?
Check your urine color. Pale yellow means well-hydrated; dark yellow or amber means drink more. Thirst is also a reliable signal for most people.
Does the 8 glasses a day rule apply to everyone?
The 8x8 rule (eight 8 oz glasses) is a rough guideline. Actual needs vary significantly by body weight, activity level, climate, and health conditions.
How accurate is this water intake calculator tool?
All processing runs entirely in your browser using verified algorithms. Results are computed with full double-precision — no server-side rounding or data transmission occurs.