Free Daily Water Intake Calculator

Staying properly hydrated is one of the most important things you can do for your overall health, energy levels, and metabolism. However, the old "8 glasses a day" rule doesn't apply to everyone. Our free Daily Water Intake Calculator provides a personalized hydration goal based on your specific body weight and activity level.

How to Use the Water Intake Calculator

1. Choose your unit: Select between Imperial (pounds and ounces) or Metric (kilograms and milliliters) using the dropdown menu.
2. Enter your weight: Input your current body weight. Larger bodies naturally require more water to function optimally.
3. Select your activity level: Choose how often you exercise or engage in strenuous activity. You lose water through sweat, so active individuals need a higher daily intake.
4. Click "Calculate Intake": Our tool will instantly generate your personalized daily water goal, providing the result in both total ounces/milliliters and easy-to-read cups/liters.

How is Daily Water Intake Calculated?

Our calculator uses standard health and fitness formulas to estimate your baseline hydration needs:

• Baseline (Imperial): You need approximately 0.5 ounces of water per pound of body weight.
• Baseline (Metric): You need approximately 33 milliliters of water per kilogram of body weight.
• Activity Adjustment: For every level of physical activity you add, the calculator automatically adds an additional 12 ounces (or 350 ml) to compensate for water lost through sweat and increased metabolic function.