Daily water calculator
Find out in seconds how many liters of water to drink per day. We estimate it from your body weight, activity level and climate, using the clinical reference of about 35 ml per kg, with adjustments for training and heat.
Your daily water target
2.8 liters/day
Renzy tracks your water in one tap and reminds you to drink — alongside your daily calories and macros.
Rough estimate (drinking water; food adds more on top). Not medical advice.
How is your water need calculated?
We start from about 35 ml of water per kg of body weight — the most common reference for healthy adults — then add extra for physical activity (training raises sweat losses) and for a hot climate. The result is rounded and clamped to a sensible 1.5–5 L range. Note: this is drinking water; food (fruit, veg, soups) adds another 20-30%.
FAQ
How many liters of water per day?
There is no universal number. The "2 liters" rule is just an average — it depends on your weight, activity and heat. The calculator gives YOUR figure.
Do coffee and tea count?
Yes. The diuretic effect of caffeine at normal doses is mild, and caffeinated drinks hydrate almost as well as water. Milk and herbal teas count too; alcohol dehydrates.
How do I know if I drink enough?
The simplest sign is urine color: pale yellow = well hydrated, dark yellow = drink more. Thirst is another cue.
Can you drink too much water?
Yes, though rare. Huge amounts in a short time can dilute blood sodium (hyponatremia), which is why the calculator caps the target. Spread water through the day.