Water Intake Calculator

Find your personalised daily water intake recommendation based on your weight and activity level — in litres, millilitres and cups.

What Does This Tool Do?

Find your personalised daily water intake based on body weight, activity level and climate. More accurate than the generic "8 glasses a day" rule.

Key Features

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Personalised
Based on weight, activity and climate.
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Climate Factor
Adjusts for hot or humid environments.
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Multiple Units
Litres, mL and cups (237mL).
⚡
Instant
Immediate recommendation.

How to Use

  1. Enter your weight in kilograms.
  2. Select your activity level.
  3. Select your climate.
  4. Click Calculate Water Intake.

Frequently Asked Questions

Is "8 glasses a day" accurate?▾
Not for everyone — needs vary by weight, activity and climate. This calculator gives a personalised estimate based on medical guidelines.
Does this include water from food?▾
No — this is total fluid intake. About 20% of daily water typically comes from food. You can subtract ~500mL if you want drink-only intake.
What formula is used?▾
Base intake = Weight (kg) × 35mL × activity factor, plus a climate adjustment. Based on EFSA and WHO hydration guidelines.