Holliday-Segar Fluids Calculator
Maintenance fluid volume for children by weight
Equation & limitations
- Equation
- ≤10 kg: 100 mL/kg/day; 10–20 kg: 1000 + 50 × (kg − 10); >20 kg: 1500 + 20 × (kg − 20)
- Version
- Holliday-Segar 1957 (the classic “100/50/20” rule)
- Source
- Holliday MA, Segar WE. The maintenance need for water in parenteral fluid therapy. Pediatrics. 1957;19:823–832.
- Appropriate in
- Well children without abnormal losses, on the original 100 kcal-per-day calorie basis.
- Limitations
- A starting maintenance estimate only — it does not cover dehydration, ongoing losses, or replacement therapy.
- Modern guidance (e.g. NICE/WHO hypotonic-fluid cautions) changes fluid choice and monitoring; volume alone is not enough.
- Not appropriate for neonates or children with cardiac/renal disease without expert review.
For educational use. Results support, and do not replace, clinical judgement — check them against the patient and local guidelines.