Water Intake Calculator

Find out how much water you should drink daily

Your Details

Weight (kg)

Activity Level

Climate

Your Daily Water Intake

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Each glass = 250 ml

Total in Milliliters—

Number of Glasses (250ml)—

Number of Bottles (500ml)—

How Water Intake is Calculated

The base recommendation is approximately 35ml of water per kilogram of body weight. This is adjusted based on your activity level (exercise increases water loss through sweat) and climate (hot weather increases evaporative losses).

Activity adjustment: Add 350-1400ml based on exercise intensity
Climate adjustment: Add 0-500ml for hot/tropical climates
Other factors: Pregnancy, breastfeeding, illness, and high altitude also increase water needs

Frequently Asked Questions

How much water should I drink per day?

A general guideline is about 35ml per kg of body weight. For a 70kg person, that's about 2.5 liters. Activity and climate increase this need significantly.

Does coffee count as water intake?

Yes, moderate coffee and tea consumption contributes to daily fluid intake. However, water is the best hydration choice. Very high caffeine intake may have mild diuretic effects.

What are signs of dehydration?

Dark yellow urine, dry mouth, fatigue, dizziness, headache, and reduced urine output are common signs. Pale yellow urine indicates good hydration.

Go deeper

Read the SnoopTool guide behind this tool

The calculator gives you the number. These SnoopTool guides explain the method, the assumptions and the decision — with worked examples, data tables and FAQs.

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