FREE TOOL · EFSA 2010 · NIN-ICMR 2024

Daily Water
Intake Calculator.

Calculate your total daily fluid target and get a practical plain water drinking schedule based on body weight, activity, climate and your daily routine. Built for adults.

Calculate my water intake →

Takes under 30 seconds. No sign-up. Educational tool, not medical advice.

Weight-Based Estimate (35 ml/kg)
Activity & Climate Adjusted
9-Slot Hourly Schedule
Pregnancy & Breastfeeding
💧

Your Hydration Profile

Fields marked * are required

Language / भाषा
Calculated in your browser, no data is stored or shared.

Common with kidney disease, heart failure, liver disease with fluid retention, or dialysis.

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Base = 35 ml x kg, a widely used adult weight-based estimate. Cross-checked against EFSA 2010 total-water reference values and ICMR-NIN 2024 guidance, which give adequate intakes rather than a per-kg formula.

YOUR RESULTS
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Plain Water / Day
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250 ml Glasses
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Avg / Waking Hour
Complete the form
Plain water to drink / day
—
litres per day
Your drinking schedule adds up to this.
Total fluid / day
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litres per day
Includes water from tea, milk, soup, fruit and vegetables.

About this tool

Most water calculators give you one number and leave you guessing whether tea and food count toward it. This one separates the two figures that actually matter: your total daily fluid target, which includes the water in tea, milk, soup, fruit and vegetables, and your plain water target, which is what you need to pour and drink once food moisture is accounted for. The timed schedule is built from the plain water figure, so the slots add up to what you actually have to drink.

WHAT YOU GET

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Daily Litres TargetPersonalised to your body weight
🥛
Glasses Per DayPractical 250 ml glass count
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Hourly Schedule9-slot timed drinking plan
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Climate AdjustmentAccounts for heat & humidity
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Drinking RemindersBrowser notification alerts
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PDF ReportSave and share with your doctor

NEED MORE?

Get a Full
Nutrition Plan

Pair your hydration goal with a personalised diet plan, built around your body weight, activity, and Indian food preferences.

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BASED ON

EFSA 2010Dietary Reference Values for Water
NIN-ICMR 2024Indian Dietary Guidelines, Guideline 14
BDAFluid and hydration recommendations
ACSMExercise hydration guidelines

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Frequently Asked Questions

How much water should I drink daily?

There is no single figure for everyone. EFSA gives adequate intakes for total water of about 2.0 litres a day for women and 2.5 litres a day for men, counting drinking water, other beverages and the water in food, under moderate temperature and activity. This calculator personalises that starting point using your body weight, activity level and climate, then separates the total fluid figure from the plain water you actually need to drink.

How do I calculate water intake by body weight?

A common adult rule of thumb is about 30 to 35 ml of fluid per kilogram of body weight per day. For a 70 kg adult, 35 ml/kg gives roughly 2.45 litres of total fluid before any adjustment for exercise or heat.

Treat it as a starting estimate rather than a precise requirement. It takes no account of body composition, and flat per-kilogram formulas tend to overestimate at higher body weights, because fat tissue holds much less water than lean tissue.

What is the difference between total fluid and plain water?

Total fluid is everything that contributes water: plain water, tea, coffee, milk, buttermilk, soups, and the moisture in fruit and vegetables. Plain water is only what you drink as water. Food typically supplies about 20 percent of daily fluid, so your plain water target is lower than your total fluid target. This calculator shows both, and builds the drinking schedule around the plain water figure.

Do tea and coffee count toward daily water intake?

Yes. For habitual drinkers, moderate tea and coffee intake contributes to daily fluid and does not need to be compensated for with extra water. The older advice that caffeine dehydrates you is not supported for moderate intakes in regular consumers. Very high caffeine intakes have a mild short-term diuretic effect, and sugary drinks bring other issues, so plain water, buttermilk and unsweetened drinks remain the better everyday choices.

Can you drink too much water?

Yes. Drinking far more than you lose can dilute blood sodium and cause hyponatraemia, which can be serious. Risk rises when large volumes of plain water are drunk quickly, or when heavy sweat losses are replaced with water alone and no sodium. Spread intake through the day, respect thirst rather than forcing volume, and include electrolytes when sweating heavily. Anyone told by a doctor to limit fluids should follow that limit instead of a calculated target.

How much water should I drink in hot weather or during exercise?

Heat and exercise both raise sweat losses, and this calculator adds up to 950 ml a day for very hot conditions and up to 1200 ml a day for intense training. These are averages: individual sweat rates vary widely, so if you sweat heavily, train outdoors or exercise for more than 60 minutes you may need more, plus sodium.

For structured training, a sweat-rate test that weighs you before and after a session gives a far more accurate figure than any weight-based estimate. Our sports hydration calculator does exactly that.

Why trust this calculator?

Built on published reference values for total water intake (EFSA 2010) and Indian dietary guidance (ICMR-NIN 2024), combined with weight-based estimation, activity and climate adjustment, and practical drinking-behaviour principles. Written and reviewed for general wellness education by DietXP. Where a figure could not be traced to a primary source, the wording says so rather than implying a citation.

Last reviewed: July 2026

⚕️ For educational purposes only, designed for adults aged 18 and above. Children's fluid needs are different; a paediatrician should be consulted for a child. Individual fluid requirements vary. People with kidney disease, heart failure, or other medical conditions must follow their physician's fluid guidelines. Not a substitute for professional medical advice.

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