Water Intake Calculator
A daily water target based on your weight, exercise and climate.
Suggested daily fluid
Rule of thumb: ~33 ml per kg of body weight, plus extra for exercise and heat. Needs differ — follow medical advice if you have a health condition.
For information only — not a diagnosis or medical advice. Nothing you enter is sent or stored.
How to use Water Intake Calculator
- Enter your weight.
- Add your daily exercise minutes and choose the climate.
- Click “Calculate” to get your daily target.
Frequently asked questions
Does tea, coffee or food count?
Yes. All drinks and water-rich foods like fruit and soup contribute. The target is total fluid, not only plain water.
Can I drink too much?
Very large amounts in a short time can be dangerous. Spread drinking through the day and let thirst guide you; people with heart or kidney conditions should follow their doctor's advice.
Can this replace a doctor?
No. This tool gives general estimates and self-checks for information only. It does not diagnose anything. Please see a qualified health professional for medical advice, and seek urgent care if you feel unwell.
Is Water Intake Calculator free?
Yes. Water Intake Calculator is free to use with no sign-up and no watermark.
Is my information saved or sent anywhere?
No. Everything is calculated in your browser. Nothing you enter is sent to a server or stored.
Does it work on my phone?
Yes. It works in any modern browser on Windows, Mac, Linux, Android and iPhone. Very large files may be slow on older phones.