IV Infusion Rate Calculator
Calculate hourly pump rates (mL/hr) and gravity drip rates (gtt/min) from fluid orders, or convert weight-based drug doses (mcg/kg/min, mg/kg/hr) to pump flow rates.
Use the IV Infusion Rate Calculator
Calculation Parameters
Use the value printed on the exact administration-set package.
Enter the infusion parameters and click Calculate.
Infusion Rate
Calculation Breakdown
Educational reference only. Verify all medication orders, concentrations, and pump programming against clinical protocols before administration.
Governing Formulas & Drop Factors
Rate (mL/hr) = Volume (mL) ÷ Hours
gtt/min = [Volume (mL) × Drop Factor] ÷ Minutes
| Tubing Type | Drop Factor | Important note |
|---|---|---|
| Macrodrip set | Commonly 10, 12, 15, or 20 gtt/mL | Confirm the exact package label |
| Microdrip Set | Commonly 60 gtt/mL | Confirm the exact package label |
• Unit standard: 1 lb = 0.45359237 kg; 1 mg = 1,000 mcg; 1 hr = 60 min.
• Gravity limitations: Actual flow can change with fluid properties, equipment and patient factors. Follow the prescription, product labeling and institutional policy; use the required approved delivery device.
• Primary references: NCBI Nursing Skills: IV infusion by gravity; Queensland Health medication calculation formulae; NHS infusion calculations.
Summary
Calculate hourly pump rates (mL/hr) and gravity drip rates (gtt/min) from fluid orders, or convert weight-based drug doses (mcg/kg/min, mg/kg/hr) to pump flow rates.
How it works
- Select calculation mode: Dose → Rate (weight-based), Rate → Dose (back-calculation), or Volume & Drip (fluid volume over time).
- In Dose → Rate mode: enter patient weight (kg or lb), prescribed dose, and bag concentration.
- In Rate → Dose mode: enter current pump rate (mL/hr), patient weight, and bag concentration to determine active delivery.
- In Volume & Drip mode: enter total volume (mL), infusion time (hours or minutes), and the drop factor printed on the tubing package.
- Click Calculate to see the hourly pump setting, gravity drip rate, and step-by-step arithmetic breakdown.
Use cases
- Program volumetric infusion pumps (mL/hr) for hydration fluids and secondary piggybacks.
- Calculate gravity drip rates (drops/minute and drops/15 seconds) when electronic pumps are unavailable.
- Calculate pump rates for a verified weight-based medication order and known bag concentration.
- Back-calculate the delivered mcg/kg/min dose from an existing pump setting for an independent arithmetic check.
- Double-check clinical math for nursing pharmacology and dosage calculation examinations.