Maintenance Fluid Calculator
Estimate routine maintenance IV fluid requirements from body weight using the pediatric Holliday–Segar method or an adult weight-based daily range.
Enter patient details
Result
Enter the patient’s weight to estimate routine maintenance fluid.
Pediatric 4–2–1 rule
The hourly shortcut gives 4 mL/kg/hour for the first 10 kg, 2 mL/kg/hour for the next 10 kg, and 1 mL/kg/hour above 20 kg.
Adult maintenance
Routine adult maintenance is commonly estimated at 25–30 mL/kg/day, with lower amounts considered for some older, frail, cardiac, or renal patients.
Reassess frequently
Clinical status, urine output, fluid balance, weight, glucose, and electrolytes should guide ongoing prescriptions rather than the initial estimate alone.
Frequently asked questions
What is the Holliday–Segar formula?
For children, it estimates 100 mL/kg/day for the first 10 kg, 50 mL/kg/day for the next 10 kg, and 20 mL/kg/day for each kilogram above 20 kg.
Is the 4–2–1 rule the same calculation?
It is the commonly used hourly approximation of the pediatric daily formula: 4 mL/kg/hour for the first 10 kg, 2 for the next 10 kg, and 1 above 20 kg.
Does this calculate fluid boluses?
No. It calculates routine maintenance only and must not be used to determine resuscitation boluses or dehydration-deficit replacement.
Can this be used for newborns?
Neonatal maintenance varies by postnatal age, gestation, clinical condition, and local protocol. This calculator is not designed for neonatal prescribing.
This tool is for educational and informational purposes only and does not constitute medical advice, diagnosis or treatment. Always consult a qualified healthcare professional for clinical decisions. VisionVix accepts no liability for decisions made based on this tool's output.
