Water is essential for nearly every bodily function, from regulating temperature to transporting nutrients and removing waste. Your daily water needs depend on your weight, activity level, climate, and overall health.
Physical Performance - Even mild dehydration (1-2% body weight loss) can impair performance, reduce endurance, and increase fatigue.
Cognitive Function - Dehydration affects concentration, alertness, short-term memory, and mood.
Metabolic Health - Adequate hydration supports metabolism, aids digestion, and helps with weight management by increasing satiety.
Temperature Regulation - Water helps maintain body temperature through sweating and respiration.
Detoxification - Water flushes toxins through the kidneys and supports liver function.
This calculator uses evidence-based guidelines:
Base Intake: 30-35 ml per kg of body weight
Activity Adjustment: Additional 350-500 ml per 30 minutes of exercise
Climate Adjustment:
Mild Dehydration:
Moderate to Severe Dehydration:
Timing:
Sources:
Monitoring:
Pregnant/Breastfeeding Women: Need an additional 300-700 ml per day
Elderly: May have reduced thirst sensation and need to drink on schedule
Illness: Fever, vomiting, or diarrhea significantly increase water needs
High Altitude: Increased respiration and urination require more water
High Protein Diets: Extra water needed to process protein and remove nitrogen waste
This calculator is for informational and educational purposes only. Individual water needs vary based on many factors. Consult with a healthcare provider if you have medical conditions affecting fluid balance (kidney disease, heart failure, etc.) or take medications that affect hydration.