Free Water Deficit Calculator
Estimate the water deficit in high sodium (hypernatraemia) using body water fraction.
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This formula is for clinicians managing high sodium; it is not a self-treatment guide. Correct sodium slowly under medical supervision.
Medical disclaimer: This tool is for education and is not medical advice. Read more.
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Frequently asked questions
What does the Free Water Deficit Calculator do?
Estimate the water deficit in high sodium (hypernatraemia) using body water fraction. 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: free water deficit formula; high sodium water calculation; hypernatremia water deficit.