H2O

Water Intake Calculator

Daily water goal based on body weight.

Daily water
Rule

Get a daily water goal from body weight

This guide uses about 35 ml of water per kilogram of body weight. It is a simple starting point, not a medical prescription.

Heat, exercise, and health conditions can raise or lower what you actually need.

Enter weight above to see a daily litre target.

water intake calculator FAQ

How do I use this Water Intake Calculator?

Fill in the fields above. The result updates as you type. Empty fields stay blank until you enter a valid number or text.

Is the Water Intake Calculator free?

Yes. Every SmartToolX calculator and converter is free. There is no paywalled result.

Does this Water Intake Calculator save my data?

No. Inputs stay in your browser unless a tool needs a public API, such as live currency rates or QR image rendering.

How accurate is this Water Intake Calculator?

We use the same published formulas you would expect from a standard water intake calculator. Always double-check medical, legal, or large money decisions.