This water intake calculator estimates how much water you should drink each day, based on your body weight. Enter your weight above for a daily target.
Formula (guideline)
Daily water ≈ 35 mL × body weight (kg)
Example
70 kg: 35 × 70 = 2,450 mL ≈ 2.45 L/day.
Needs rise with exercise, heat, and illness. Food and other drinks also contribute to your total fluid.
Important
This tool is for general educational purposes only and is not medical advice, diagnosis, or treatment. It does not replace evaluation by a qualified healthcare professional — consult one for any health decision. Last updated: August 2026.
Frequently Asked Questions
How much water should I drink a day?
A common guideline is about 35 mL per kg of body weight — roughly 2.5 L for a 70 kg adult — adjusted for activity and climate.
Does this include water from food?
Food provides some fluid, so your drinking target can be a little lower; this figure is a simple starting guideline.
Can I drink too much water?
Yes, very rarely. Extremely high intake in a short time can be harmful; drink to thirst and adjust for activity.