Fluid Deficit Calculator
Reviewed by Hamza Gujjar, Algorithm Architect & Software Developer
Last updated: July 28, 2026Fluid Deficit Calculator
Estimating fluid therapy needs for a dehydrated patient? This calculator applies the standard fluid deficit formula.
Fluid Deficit (L) = Body Weight(kg) x (Dehydration % / 100)
Example
A 20 kg patient, estimated 8% dehydration:
Fluid Deficit = 20 x 0.08 = ~1,600 mL
Where the Dehydration Percentage Comes From
This standard formula estimates fluid deficit from an estimated dehydration percentage, typically assessed by a veterinarian through skin turgor (skin tent test), mucous membrane moisture, and other clinical signs during a physical exam.
A Reference Calculation, Not Treatment Guidance
This is a general reference calculation only, not a substitute for veterinary assessment and fluid therapy planning - actual fluid therapy protocols also account for ongoing losses, maintenance needs, and the patient's cardiac and renal status, all of which require professional veterinary evaluation.