Daily Water Intake Calculator

How much water should you drink daily

Exact water needs depend on body weight, physical activity level, climate, and overall health. The basic formula is approximately 30-35 ml of water per kg of body weight per day, with additional adjustments for exercise and heat.

Why water matters

• Thermoregulation: water helps your body cool down through sweating.
• Nutrient transport: blood, which is 90% water, delivers oxygen and nutrients to cells.
• Joint function: water is part of synovial fluid, which lubricates joints.
• Athletic performance: even 2% dehydration can significantly reduce endurance and strength.

Factors affecting water needs

• Physical activity: exercise increases fluid loss through sweat, so you need more water.
• Climate: hot weather increases sweating even without exercise.
• Diet: a high-protein diet and caffeine can slightly increase water needs.

How to spot signs of dehydration

• Urine color: dark yellow is a signal to drink more water; light yellow or clear indicates adequate hydration.
• Thirst: feeling thirsty already indicates mild dehydration — it's better to drink regularly rather than wait for thirst.
• Fatigue and headache: even mild dehydration can cause tiredness, reduced concentration, and headaches.
• Dry skin and lips: another visible sign of insufficient fluid intake.

Fluid sources that count toward your total

Your daily target includes not just plain water, but other fluids too: tea, coffee, juice, soups, and water content in fruits and vegetables (watermelon, cucumber, oranges contain up to 90-95% water). Caffeinated drinks have a mild diuretic effect but still count toward your overall fluid balance.

This is an estimate. Individual needs may vary depending on health conditions (for example, kidney or heart disease requires a different approach to fluid intake) — consult a doctor for specific medical conditions.