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Free nursing calculation tool

Nursing Intake & Output Calculator

Calculate intake, output, net fluid balance, and urine output. Convert common fluid units, build a private simulated shift log, and practise I&O cases without entering patient identifiers.

Intake versus output totals Explicit fluid conversions Printable worksheets
One reporting period

Quick intake and output total

Enter category totals. Each value is converted to mL before it is added.

Intake
Output
Results dashboard

Fluid totals

Numerical summary only—not a clinical interpretation.

Total intake740 mL
Total output400 mL
Positive net balance+340 mL

A positive, negative, or zero balance is a calculation—not an automatic “normal” or “abnormal” label. Meaning depends on the reporting period and clinical context.

Intake by category

Oral intake
240 mL
IV intake
500 mL

Output by category

Urine output
400 mL
Core formula

How to calculate intake and output

First convert every measurable entry to the same unit—usually milliliters. Add intake sources, add output sources, and subtract total output from total intake for the selected reporting period.

Net fluid balance = total intake − total output

A plus or minus sign describes the arithmetic direction only. It does not tell you whether the balance is appropriate for a particular person.

Documentation checklist

What counts as intake and output?

Record distinct measurable sources rather than combining them into an unexplained total. OpenStax describes totaling I&O by reporting periods such as a shift, with frequency determined by facility policy.

Common intake sources

  • Oral fluids and qualifying melting foods
  • Enteral feeding and free-water flushes
  • IV primary fluids and piggybacks
  • Blood products
  • Medication carrier volume
  • Tube, line, and irrigation flushes

Common output sources

  • Urine
  • Emesis and liquid stool
  • NG or gastric suction
  • Surgical and wound drains
  • Chest tubes
  • Other measurable losses
Conversion reference

Common nursing fluid conversions

The calculator shows every conversion before an entry is added, so the original unit and milliliter value remain visible.

1 cc=1 mL
1 fl oz≈30 mL
1 cup≈240 mL
1 tsp≈5 mL
1 tbsp≈15 mL

Ice chips: keep the percentage visible

Educational examples often count ice chips as half their measured volume. Because documentation rules can differ, the shift logger displays a configurable percentage instead of applying an invisible assumption.

Separate calculation

Urine output in mL/hr and mL/kg/hr

Hourly urine output equals measured urine volume divided by collection hours. If weight is included, divide again by kilograms. Keep the numerical result separate from interpretation.

mL/hr = urine volume ÷ hoursmL/kg/hr = urine volume ÷ weight ÷ hours
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Privacy and safety

A teaching aid, not a clinical record

Do not enter a patient name, birth date, room number, medical-record number, or other identifier. Shift entries are stored only in the browser and automatically expire after 12 hours, but this tool does not replace the EHR, official documentation, clinical assessment, or facility policy.

Common questions

Intake and output calculator FAQs

How is net fluid balance calculated?

Add all measurable intake, add all measurable output, then subtract total output from total intake. A result above zero is a positive net balance, below zero is a negative net balance, and zero means the recorded totals are equal. Those labels are mathematical descriptions, not clinical interpretations.

What counts as intake on an I&O worksheet?

Examples include oral fluids, enteral feeding and free water, IV fluids, blood products, medication carrier volume, tube or line flushes, and other measurable fluid sources. Foods that melt at room or body temperature may count, but documentation rules follow facility policy.

What counts as output?

Measurable output can include urine, emesis, liquid stool, NG suction, surgical drains, chest tubes, wound drainage, and other measurable losses. Categories and reporting frequency should follow the authorized documentation system and facility policy.

How do you convert ounces and cups to milliliters for nursing I&O?

A common educational conversion is 1 fluid ounce equals approximately 30 mL. One cup is 8 fluid ounces, or approximately 240 mL. One cubic centimeter equals 1 mL.

How are ice chips counted as intake?

Many educational examples count ice chips as half their measured volume after melting, but practices can vary. This calculator never hides that assumption: the percentage is visible and configurable for each ice-chip entry.

Does this calculator store patient information?

The tool does not request patient identifiers or send shift entries to a server. Shift entries stay in the current browser and automatically expire 12 hours after the latest change. It is not an EHR or official clinical record, so users should not enter names, dates of birth, room numbers, or record numbers.

What does a urine output result mean?

The tool calculates mL/hr and, when weight is supplied, mL/kg/hr. It does not label the result as normal or abnormal. Duration, age, condition, medications, measurement accuracy, and other clinical findings affect interpretation.

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Sources

Safety notice: Calculated totals and general educational references do not diagnose fluid deficit, fluid excess, kidney injury, or another condition, and they do not recommend treatment. Follow the authorized care plan, documentation system, escalation process, and facility policy.