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Water Intake Calculator

Find out how much water you should drink daily based on your weight, exercise, and climate.

30 kg150 kg
None180 min

Daily Water Intake

3.1L

13 glasses · 3,110 ml · 3.1 bottles (1L)

Daily target vs 12-glass reference

13 / 12 glasses (250ml each)

Intake Breakdown

Base (weight-based)

2450 ml

70 kg × 35 ml

Exercise

+360 ml

30 min × 12 ml

Climate

+300 ml

+300 ml

Based on 35ml/kg body weight guideline. Individual needs vary based on health conditions, diet, and climate. Thirst is a reliable indicator - don't ignore it.

About the Water Intake Calculator

Mild dehydration - as little as 1-2% body water loss - impairs cognitive performance, reduces physical endurance, and triggers headaches. Yet most Indians are chronically under-hydrated, partly because thirst is a lagging indicator. The recommended intake varies by body weight, activity level, and climate - a 90 kg construction worker in Chennai needs 3-4x more water than a 50 kg office worker in Shimla. This calculator personalizes your daily water target.

Daily Water Intake Calculation

Base intake = 35 ml × body weight (kg) · Add for exercise: 500 ml per 40 min of moderate exercise · Add for hot climate: 600 ml for temperatures above 32°C

Base: 35 ml/kg is the standard clinical guideline · Exercise addition: 500 ml per 30-40 min activity · Hot climate addition: 300-600 ml · Total: typically 2-4 liters for most Indian adults

Worked Example

70 kg male, 45 min gym workout, normal climate

Body weight:70 kg
Exercise:45 min moderate intensity
Climate:Normal (25-30°C)

Base = 70 × 35ml = 2,450 ml · Exercise addition = 500 ml · Total ≈ 2.95L/day (approx 12 glasses of 250ml)

Tips & Insights

  • 1

    Urine color is the simplest hydration check - pale yellow means you are well hydrated; dark yellow means drink more.

  • 2

    Coffee and tea count toward hydration despite being caffeinated - contrary to popular belief, the mild diuretic effect is offset by the water content.

  • 3

    Drink 500ml of water 30 minutes before each meal - it aids digestion and reduces calorie intake naturally.

  • 4

    In Indian summers (40°C+), water needs can increase by 1-1.5 liters over the base calculation.

  • 5

    Electrolytes matter in intense heat or exercise - add a pinch of salt and lemon to water, or use ORS sachets.

Why this matters for you

Dehydration is one of the most common, most preventable causes of poor concentration, fatigue, and kidney stones. India has one of the highest rates of kidney stone incidence globally, and low water intake is a primary risk factor. At a population level, improving hydration is among the cheapest, most effective public health interventions available.

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