About this calculator
This calculator estimates an oral rehydration solution (ORS) planning volume for children with diarrhoea who are able to drink. It is designed for education and caregiver-clinician conversations, not for severe dehydration or emergency symptoms.
Use prepared ORS when possible. Continue breastfeeding or normal feeding when appropriate, and seek urgent care if the child is lethargic, unable to drink, has signs of shock, has persistent vomiting, has blood in stool, or produces very little urine.
Uses weight-based ORS planning for some dehydration: 75 mL/kg over about 4 hours, with separate prompts for ongoing losses and urgent care red flags. This is educational and does not replace a clinician.
Source-mapped; urgent red flags built in
ORS estimates are not enough for severe dehydration, shock, altered mental status, blood in stool, green vomit, severe abdominal pain, or inability to keep fluids down.
Formula and method
For some dehydration, the calculator uses ORS volume = 75 mL × body weight in kg over about 4 hours. For children without obvious dehydration, it shows a conservative ongoing-loss prompt after loose stools rather than a diagnosis. Red-flag contexts route to urgent clinical care instead of a self-care plan.
Limitations and when not to rely on this result
- ORS estimates are not enough for severe dehydration, shock, altered mental status, blood in stool, green vomit, severe abdominal pain, or inability to keep fluids down.
- Infants, medically complex children, and children with diabetes, kidney disease, or significant ongoing losses need individualized clinical advice.
- This page does not replace urgent assessment when red flags are present.
Frequently asked questions
How much ORS does this calculator estimate? +
For some dehydration, it estimates 75 mL per kg over about 4 hours, then recommends reassessment. This is a planning estimate, not a diagnosis.
When should I seek urgent care instead of using ORS at home? +
Seek urgent care for lethargy, confusion, signs of shock, inability to drink, repeated vomiting, blood in stool, green vomit, severe abdominal pain, very low urine, or concern in a young infant.
Can I use water instead of ORS? +
Plain water does not replace the electrolytes lost with diarrhoea. Prepared ORS is preferred when rehydration is needed.
Should feeding continue during diarrhoea? +
Guidelines generally support continued feeding and breastfeeding when the child can tolerate it, but severe illness or vomiting needs clinical advice.
Does this calculator treat dehydration? +
No. It only estimates educational ORS volumes. A clinician should assess children with moderate, severe, persistent, or uncertain dehydration.