Total Body Water Calculator
Estimate your body water using the Watson formula.
Your result
Typical adult body water is about 50–65% of body weight. Water share falls as body fat rises.
Medical disclaimer: This tool is for education and is not medical advice. Read more.
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Frequently asked questions
What does the Total Body Water Calculator do?
Estimate your body water using the Watson formula. Enter your values and the result and chart update instantly.
How accurate is it?
It uses published, widely used formulas. Results are estimates for education and planning, not a diagnosis. Talk to a qualified clinician about decisions affecting your health.
Is my information stored or shared?
No. All calculations run in your browser and nothing you type is sent to a server or saved.
What can I search to find this tool?
People find it by searching for: how much water is in my body; body water percentage; watson total body water.