Daily Water Intake Calculator

A simple approach estimates daily ounces from body weight and adds a small adjustment based on activity level.

Key formula: water_oz = weight_lbs * 0.5 + (activity_score / 40) * (weight_lbs * 0.2)

Example values: weight = 150 lbs, activity = Moderately Active (score 20).

Calculate base intake: 150 × 0.5 = 75 oz.
Compute activity factor: 20 / 40 = 0.5, activity adjustment = 0.5 × (150 × 0.2) = 15 oz.
Add together: 75 + 15 = 90 oz daily water.
Convert to liters: 90 oz × 0.02957 ≈ 2.66 L.

Ounces match common bottle sizes and many U.S. recommendations; the calculator also provides a liter conversion for international use.

Higher activity increases fluid losses, so we apply a proportional adjustment using the activity score to raise the recommended intake.

Pregnant or nursing individuals often need more fluids; consult a healthcare provider for personalized guidance.

Distribute intake evenly across the day, and increase intake around workouts or in hot conditions rather than consuming large amounts at once.

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