Daily Water Intake Calculator
Get a personal estimate of how much water to drink each day, based on your body weight, exercise and whether it’s hot where you live.
Your result appears here.
By Shah Rukh, software developer · Last updated:
How the estimate works
A common rule of thumb is about 33 ml of water per kg of body weight per day, plus roughly 350 ml for every 30 minutes of exercise, and extra in hot weather. Health authorities such as the US National Academies suggest a total water intake (from all drinks and food) of about 3.7 litres a day for men and 2.7 litres for women.
Signs you’re drinking enough
- Pale yellow urine.
- Rarely feeling thirsty.
- No headaches or tiredness from dehydration.
Tea, coffee, milk, fruit and vegetables all count toward your daily water.
This is an estimate for general information, not medical advice. Talk to a doctor or registered dietitian before making big changes.
Frequently asked questions
Is 8 glasses a day right for everyone?
It’s a simple guide, but needs vary with body size, activity, climate and health.
Can I drink too much water?
Yes, although it’s rare. Drinking extreme amounts in a short time can be dangerous. Spread your intake through the day.
Do people with medical conditions need different amounts?
Yes. Some heart and kidney conditions require fluid limits, so follow your doctor’s advice.
Related tools
BMI Calculator
Check your body mass index in kg/cm or lb/ft and see your healthy weight range.
TDEE & BMR Calculator
Daily calorie needs and basal metabolic rate.
Macro Calculator
Split calories into protein, carbs and fat.
One Rep Max Calculator
Estimate your 1RM and training percentages.
Sleep Calculator
Best bedtime or wake-up time using 90-minute cycles.
Pregnancy Due Date Calculator
Estimated due date and current week of pregnancy.