Daily Water Intake Calculator
Find out how much water you need per day based on your body weight, activity, and Indian climate. Get a practical hourly drinking schedule.
How Full Your Day Should Be
—Hourly Drinking Schedule
Spread your intake evenly across waking hours
India-Specific Hydration Tips
What is the Water Intake Calculator?
The Water Intake Calculator helps you determine your optimal daily hydration target based on your body weight, physical activity level, and the climate you live in. Staying properly hydrated is essential for nearly every bodily function — from regulating body temperature and transporting nutrients to maintaining kidney health, joint lubrication, and cognitive performance. Dehydration of even 1–2% of body weight impairs physical performance and concentration. However, the popular "8 glasses a day" rule is an oversimplification — actual needs vary significantly by individual. This calculator uses a weight-based formula adjusted for activity and Indian climate conditions, giving you a personalised daily water target in millilitres, litres, and glasses, along with a practical hourly drinking schedule. Whether you live in Chennai's humid heat or Shimla's cool hills, this tool accounts for your environment.
How to Use the Water Intake Calculator
- 1. Select your unit system (metric kg or imperial lbs) and enter your body weight.
- 2. Choose your activity level — sedentary, moderately active, active (exercise daily), or intense training.
- 3. Select your climate zone: temperate hill station, normal India, hot and humid coastal, or extreme desert heat.
- 4. Check any special conditions that apply (pregnant, breastfeeding, fever/illness).
- 5. Click "Calculate My Intake" to get your daily target in ml, litres, and glasses, plus an hourly schedule.
How Water Needs Are Calculated
Formula
Base = Weight(kg) × 35 ml
Total = Base + Activity bonus + Climate bonus + Special conditions bonus
The WHO and ICMR both recommend 8–10 glasses (2–2.5 litres) per day as a general guideline, but individual needs vary with body size, weather, and health status.
Frequently Asked Questions
How much water should I drink daily?
A general guideline is 35 ml per kilogram of body weight as a baseline. A 70 kg adult needs approximately 2,450 ml (8–10 glasses) per day under normal conditions. Increase by 400–600 ml for exercise sessions and 500–1,000 ml in hot weather. Individual needs also vary with health conditions, dietary water content, and sweat rate.
Does coffee or tea count toward daily water intake?
Yes — caffeinated drinks like coffee and tea do contribute to total fluid intake. Despite being mild diuretics, the water they contain outweighs the fluid lost. However, plain water, coconut water, and low-sugar beverages are preferable for hydration since they provide fluids without added calories, sugar, or stimulants.
What are the signs of dehydration?
Early signs include dark yellow urine, dry mouth, fatigue, and mild headache. Moderate dehydration causes dizziness, reduced urine output, and muscle cramps. Severe dehydration leads to rapid heartbeat, confusion, and fainting. The simplest check: urine should be pale straw-coloured. Very dark urine is a reliable sign you need water immediately.
Does climate affect how much water I need?
Yes, significantly. In hot and humid conditions — common across India during summer months — you can lose 1–2 litres per hour through sweating during physical activity. People in coastal states or working outdoors should add 500–1,000 ml beyond their baseline. Altitude also increases needs due to faster respiration and moisture loss through breathing.