How to use the daily water intake calculator
Estimate daily water needs from weight and activity. Enter weight, exercise in the fields above; the water needed, glasses (250 ml) are computed instantly and plotted on the chart so you can see how the answer changes.
Formula
Variables
- w — Weight (kg)
- ex — Exercise (min/day)
Worked example
With weight = 70 kg, exercise = 30 min/day, the calculator gives water needed ≈ 2.66 L/day; glasses (250 ml) ≈ 10.64.
Frequently asked questions
What is the formula for the daily water intake calculation?
Water needed (L/day) = w × 0.033+ex / 30 × 0.35. Glasses (250 mL) = [Water needed] × 4. Here w is weight (kg), ex is exercise (min/day).
What inputs do I need for the daily water intake calculator?
You need weight in kg, exercise in min/day. Each field is pre-filled with a typical example so you can see how the result responds as you edit the numbers.
How do I use this calculator?
Type values into the input fields. Results and the chart update instantly. Use Reset to restore the example values, Copy results to paste them elsewhere, or Share to copy a link that preserves your inputs.
Is the result exact?
Calculations use standard formulas and double-precision arithmetic, then display about seven significant figures. Real-world measurements carry uncertainty, so treat results as estimates unless your inputs are exact.