Water Intake Calculator

Free water intake calculator. Find out how much water you should drink daily based on your weight and activity level.

How the Water Intake Calculator works

Base water needs are estimated at 35 ml per kilogram of body weight. Additional water is added for exercise—roughly 12 ml per minute of activity—to account for fluid lost through sweat and respiration.

Formula

Water (L) = Weight(kg) × 0.035 + Exercise(min) × 0.012

How to use the Water Intake Calculator

  1. 1The water intake calculator is designed to be simple and fast.
  2. 2Enter your body weight.
  3. 3Select your daily exercise duration.
  4. 4See your recommended water intake.
  5. 5Your result is shown immediately.

Examples

  • 70 kg, 30 min exercise = 2.8 liters/day
  • 154 lb, 60 min exercise = 3.4 liters/day

Benefits

  • Completely free with no signup required.
  • Runs entirely in your browser for instant results and privacy.
  • Works on mobile, tablet and desktop.
  • Results can be copied with one click.

Frequently Asked Questions

Is the water intake calculator free to use?

Yes. The water intake calculator is 100% free, with no signup, no watermark and no hidden limits.

Does the water intake calculator store my data?

No. All calculations and processing happen locally in your browser. Nothing is uploaded to a server.

Does the water intake calculator work on mobile?

Yes. The water intake calculator is fully responsive and works on phones, tablets and desktop computers.

How is daily water intake calculated?

Base intake is 35ml per kg of body weight, plus additional water for exercise (about 350ml per 30 minutes of activity).

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