Water intake calculator
Get a rough daily water target based on your weight and activity.
Per day
2.4 L
Roughly
10 cups
An estimate, not medical advice. Runs entirely in your browser.
How to use this tool
- Enter your weight and how many minutes you exercise on a typical day.
- Click Calculate for a daily target in liters and cups.
The formula
A common guideline is about 35 milliliters of water per kilogram of body weight, plus extra for exercise. This tool adds roughly 350 milliliters for each 30 minutes of activity.
base = weight kg x 35 ml
exercise = minutes / 30 x 350 ml
total = base + exercise
A real example
At 70 kilograms with 30 minutes of exercise, the target lands around 2.4 liters. Hot weather, illness, and pregnancy raise the need, so treat the number as a starting point and listen to your body.
Common questions
Does coffee or tea count?
Most fluids contribute to hydration, and water-rich foods help too. The figure here is a simple guide for plain water intake.