Intake and output calculator (fluid balance)
Enter your values. The answer and the full worked solution update as you type.
Result
| Item | Intake (mL) | Output (mL) |
|---|---|---|
| Oral fluids | 1200 | |
| IV fluids | 1000 | |
| IV medications and flushes | 150 | |
| Ice chips (volume of the chips, counted as half) | 100 | |
| Urine | 1650 | |
| Nasogastric aspirate | 200 | |
| Wound drains | 150 |
Insensible losses (skin and breathing) are not measured; add an estimate under other output only when the question asks for it. For exam practice only. This is a study aid, never a clinical decision: always follow the prescription, local protocols and the product information.
Add up a patient’s intake and output (I&O) and find the fluid balance, as on a nursing fluid chart. Enter oral and IV fluids, IV medicines, tube feeds, ice chips and blood products as intake, and urine, emesis, nasogastric aspirate, drains and liquid stool as output. The calculator gives the totals, the positive or negative balance and the urine output per hour and per kg.
Step-by-step solution
Total intake
Total output
Fluid balance = intake − output
Urine output per hour
Key formulas
- Fluid balance
- intake − output
- Ice chips
- count as half their volume
- Urine output
- mL/kg/h = mL / (kg × h)
How to calculate intake and output
- Add every intake for the period: oral fluids, IV fluids, IV medications and flushes, tube feeds and water flushes, and blood products.
- Count ice chips as half their volume, because melted ice chips give about half their volume as water.
- Add every measured output: urine, vomit, nasogastric aspirate, drains and liquid stool.
- Fluid balance = total intake − total output. A positive balance means fluid retained, a negative balance fluid lost.
- Urine output per hour = urine ÷ hours; divide by the weight in kg for mL/kg/h.
Questions and answers
Why are ice chips counted as half?
Ice takes up more space than the water it melts into, and chips leave gaps between them, so a cup of ice chips gives roughly half its volume as water. Nursing courses use this 50% rule.
What urine output is too low?
Exam questions often use less than 0.5 mL/kg/h in adults (or less than about 30 mL/h) as oliguria, the urine output criterion for acute kidney injury in the KDIGO guideline. Children have higher targets, often 1 mL/kg/h.
Are insensible losses included?
No. Losses through the skin and breathing, about 500–1000 mL a day in adults and more with fever, are not measured. Add an estimate under other output only when the question asks for it.
What counts as intake?
Everything liquid that enters the body: drinks and foods that are liquid at room temperature, such as soup or ice cream, IV fluids and medicines, tube feeds and flushes, and blood products.
Practise it yourself
Practise IV fluids & fluid balance
A calculator gives the answer. In the exam you need the method: practise it with new problems, hints and worked solutions.