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Water Intake Calculator
Calculate daily water intake based on your weight and activity level.
⭐ Used by 8,760 people

The Water Intake Calculator tells you exactly how much water you should drink daily based on your body weight and activity level. Proper hydration is crucial for health.

Daily Water Recommendation

Basic Formula: 35ml × Body Weight (kg)
Example: 70kg person = 70 × 35 = 2,450ml = 2.45 litres
Activity multiplier applied for exercise level

Signs of Dehydration

  • 💛 Dark yellow urine (should be pale yellow)
  • 😴 Fatigue and low energy
  • 🤕 Headaches
  • 😵 Dizziness
  • 👄 Dry mouth and skin

Tips to Stay Hydrated

  • 💧 Drink a glass of water when you wake up
  • 💧 Carry a water bottle everywhere
  • 💧 Set hourly reminders on phone
  • 💧 Eat water-rich foods (cucumber, watermelon)
  • 💧 Drink before meals, not just when thirsty

Water Needs Increase When

  • 🌡️ Hot weather or summer season
  • 🏃 Exercising or physical activity
  • 🤒 Fever, vomiting or diarrhea
  • 🤰 Pregnancy or breastfeeding
📖 Complete Guide
Formulas, examples, tips & FAQs
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Frequently Asked Questions

How much water should I drink daily?

A common guideline is about 30 to 35 ml of water per kilogram of body weight, though needs rise with exercise, heat, and individual factors. The calculator estimates a target for you.

Does the water calculator account for activity?

Yes. More active people lose more fluid through sweat, so the calculator increases the recommended intake based on your activity level.

Do other drinks count toward water intake?

Beverages and water-rich foods do contribute to hydration, but plain water is the best choice. Limit sugary and caffeinated drinks, which are less hydrating.