Water Intake Calculator

The base recommendation starts at 0.5 fl oz of water per pound of body weight per day — metric inputs are converted to pounds first using the factor 2.20462. Activity adjustments are then added to account for fluid lost through sweat: 12 oz for moderate activity (3–4 workouts per week), 24 oz for active (5–7 days), and 36 oz for very active individuals such as athletes or those doing manual labor. Hot or humid climates add a further 16 oz to account for elevated sweat rate even at rest. The final fluid ounce total is converted to liters by multiplying by 0.0295735 (the volume of one US fluid ounce in liters), and divided by 8 to produce the equivalent number of standard 8-oz drinking cups. All three output formats represent the same daily fluid target expressed in different units.