Water Intake Calculator
Calculate your daily water needs based on your weight, activity level, and climate. Get personalized hydration targets in liters and glasses.
Spread intake across the day. Drink more before, during, and after exercise. Thirst is a lagging indicator — hydrate proactively.
Stay hydrated and track your intake with CalRay
Your hydration target is set. Use CalRay to log water intake, set reminders, and build healthy hydration habits.
Common Questions
How much water should I drink per day?
A common rule is 30–35 ml per kg of body weight per day. For a 75 kg person, that is roughly 2.5 liters. Activity, heat, and exercise increase needs. Use the calculator above for a personalized target.
Does water help with weight loss?
Yes. Drinking water before meals can increase satiety and slightly boost metabolism. Replacing sugary drinks with water also reduces calorie intake. Proper hydration supports exercise performance and recovery.
Can you drink too much water?
Excessive water intake can dilute blood sodium levels, causing hyponatremia. This is rare and usually only occurs when drinking several liters in a short time without electrolytes. Listen to your body and spread intake evenly.
Do other drinks count toward hydration?
Yes. Coffee, tea, milk, and even water-rich foods like fruits and vegetables contribute to hydration. However, alcohol and very sugary drinks can have a mild diuretic effect. Plain water remains the best choice.
What are signs of dehydration?
Common signs include dark yellow urine, dry mouth, headache, fatigue, dizziness, and decreased urine output. Severe dehydration can cause rapid heartbeat, confusion, and fainting. Drink water regularly to stay ahead of thirst.