Hydration Calculator

Calculate your daily water target based on body weight and exercise, using the 35 ml/kg baseline with an additional 500 ml per 30 minutes of physical activity.

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min

How the Calculation Works

Baseline: 35 ml × body weight (kg)

Exercise addition: 500 ml per 30 minutes of exercise

For a 70 kg person with 60 minutes of exercise: (70 × 35) + (2 × 500) = 2,450 + 1,000 = 3,450 ml/day

Hydration Tips

  • Start your day with a large glass of water.
  • Drink 400–600 ml of water 2 hours before exercise.
  • Aim for pale yellow urine — this is the simplest hydration marker.
  • Increase intake in hot weather or at altitude.
  • Eat hydrating foods — cucumbers, watermelon, and leafy greens are 90%+ water.

Water vs Sports Drinks

For most workouts under 60–90 minutes, water is sufficient. For longer or high-intensity sessions with significant sweat loss, electrolyte drinks help replace sodium and potassium.

FAQ