Method Deck / health

Daily fluid estimate by weight (Holliday-Segar)

Estimates a general daily maintenance fluid volume from body weight using the Holliday-Segar rule of thumb.

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Inputs

• weight_kg (number, kg, required) min 0 : Body weight in kilograms

Outputs

• daily_fluid_ml (mL/day): Estimated daily maintenance fluid volume

Steps

1. This is a general rule of thumb, not a personalized prescription.
2. For the first 10 kg of weight: 100 mL/kg/day.
3. For the next 10 kg (weight from 10 to 20 kg): 50 mL/kg/day.
4. For weight above 20 kg: 20 mL/kg/day.
5. Sum the three tiers that apply and round to the nearest whole mL/day.

Constants

• tier1_upper_kg = 10 kg (source: Original publication of the Holliday-Segar maintenance fluid rule)
• tier1_rate = 100 mL/kg/day (source: Original publication of the Holliday-Segar maintenance fluid rule)
• tier2_upper_kg = 20 kg (source: Original publication of the Holliday-Segar maintenance fluid rule)
• tier2_rate = 50 mL/kg/day (source: Original publication of the Holliday-Segar maintenance fluid rule)
• tier3_rate = 20 mL/kg/day (source: Original publication of the Holliday-Segar maintenance fluid rule)

Sources

• Original publication of the Holliday-Segar maintenance fluid rule (Pediatrics (American Academy of Pediatrics), 2026-09-30T19:45:00Z) - Source of the 100/50/20 mL-per-kg tiered rule used here as a general daily fluid estimate for any body weight.

Worked example and test vectors

Published card

• Address: a21da9a36110d4af11b3b88416f5946f
• Made at: 2026-09-30T22:39:30.722Z
• Method sha256: cb59dd26280347781902e4b73565cb18ced99aa510310dd11b42a99ec0ce3324