Water Intake Calculator
Estimate your daily water intake based on bodyweight, activity level, and climate — a practical starting point, not a strict prescription.
Ready to Calculate
Estimate your daily water intake based on bodyweight, activity level, and climate — a practical starting point, not a strict prescription.
Water Intake Calculator Guide
Hydration needs vary by bodyweight, activity level, climate, and individual physiology. This calculator uses a common sports-nutrition starting point — roughly 35 mL per kg of bodyweight per day — with add-ons for exercise and heat, as a practical baseline you can adjust from.
How It's Calculated
Base intake = bodyweight (kg) × 35 mL. Activity level adds 250 mL (light) to 1000 mL (extremely active) for exercise-driven sweat losses. A hot/humid climate toggle adds another 500 mL for additional heat-driven losses.
This is a general guideline, not medical advice — individual needs vary with health conditions, medications, pregnancy, and altitude. It also doesn't count water from food, which typically supplies roughly 20% of daily intake. If you have a kidney, heart, or other condition affecting fluid balance, follow your healthcare provider's guidance instead.
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Water Intake Calculator FAQ
How much water should I drink per day?
A common starting point is about 35 mL per kg of bodyweight per day, adjusted up for exercise and hot/humid climates. This calculator estimates a personalized baseline — individual needs still vary.
Does this include water from food?
No. This calculator estimates fluid intake from drinking only. Food (especially fruits, vegetables, and soups) typically supplies roughly 20% of daily water intake on top of this.
Should I drink more on training days?
Yes — select a higher activity level, or toggle the hot/humid climate option if you're training somewhere hot, to account for additional sweat losses.
Is this medical advice?
No. This is a general wellness guideline. If you have a kidney, heart, or other condition that affects fluid balance, or take medications that affect hydration, follow your healthcare provider's specific guidance instead.