Pediatric Fluid Requirement

How it is calculated

The tool applies the Holliday-Segar weight bands, with weight in kilograms. Up to 10 kg: daily = weight × 100. From 10 to 20 kg: daily = 1000 + (weight − 10) × 50. Above 20 kg: daily = 1500 + (weight − 20) × 20. Each band covers only the kilograms inside it, so the first 10 kg always count at 100 mL, the next 10 kg at 50 mL and the rest at 20 mL. The hourly rate is daily ÷ 24. Daily volume is shown in mL and the hourly rate in mL/h, both rounded to whole numbers. The tool has no upper limit on weight and does not adjust for fever, losses or illness, because it gives maintenance fluid only. Zero or negative weights give no result.

Common mistakes

• Applying 100 mL/kg to the whole weight. For a child over 10 kg the extra kilograms count at lower rates, so 18 kg is 1,400 mL, not 1,800 mL.
• Entering weight in pounds or in grams. The field is kilograms, so a 40 lb child is about 18 kg.
• Treating the result as the volume to give in an illness. This is maintenance only, and it does not cover dehydration, fever or ongoing losses.
• Using the tool for a teenager or an adult without checking. It has no upper weight limit, so for a heavy person the figure keeps rising by 20 mL per kilogram.
• Mixing up the daily and the hourly figure. The hourly rate is the daily volume spread over 24 hours, not the volume per feed or per drink.