Water Calculator

Calculate optimal daily water intake based on body weight, climate and activity level.

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Your Results

What is Water Intake Calculator?

A Water Intake Calculator computes your optimal daily fluid intake based on body weight, activity level and climate conditions. Proper hydration supports digestion, body temperature regulation, joint lubrication and cognitive function.

Formula

Base: Weight (kg) × 0.033 litres
+ Activity Add-on: 0.3–1.0L based on activity
+ Climate Add-on: 0.3–0.7L for hot/humid weather

Reference Chart

WeightSedentaryModerately ActiveVery Active
55 kg1.8L2.4L3.0L
70 kg2.3L2.9L3.5L
90 kg3.0L3.6L4.2L

How to Use

Enter weight, activity level and local climate. Click Calculate for your daily water target in litres and equivalent glasses. Adjust upward by 200–300ml for every hour of intense exercise.

Limitations

Individual needs vary based on health conditions, medications and diet. Foods also contribute 20–30% of daily fluid intake. Check urine color — light yellow indicates good hydration.