💧 Water Intake Calculator
🔒 Sicher & Clientseitig
Estimate daily water intake from body weight, with bumps for exercise and hot climates. The result is shown in milliliters, liters, and 250 ml glasses. Baseline is 33 ml per kg of body weight — typical for moderately active adults.
Estimate only. Real needs vary by sex, body composition, sweat rate, kidney function, and altitude. Drink to thirst; pale-yellow urine is the best practical indicator.
How to use
- Enter your body weight in kilograms.
- Pick activity level and climate. Heavy exercise adds 500 ml; hot climates add another 500 ml.
- Click Calculate — the daily target appears in ml, liters, and 250 ml glasses.
Formula: 33 ml × weight(kg), plus 350 ml for moderate exercise / 500 ml for heavy, plus 500 ml for hot climates. Caffeinated drinks count toward intake (not as much as water but most of the volume); alcohol is a net negative for hydration.
This estimate covers total fluid — food contributes about 20% of daily water (more if you eat lots of fruit, soup, or vegetables). Drinking ~1.5–2.5 L of water-equivalent fluids on top of food usually covers it.