IV Infusion Rate Calculator
Calculate flow rate (mL/hr) and drip rate (gtt/min) for intravenous fluids.
10 (Macro)
15 (Macro)
20 (Macro)
60 (Micro)
Flow Rate:
0 mL/hr
Drip Rate:
0 gtt/min
How to Calculate IV Infusion Rates
In clinical settings, accurately calculating the IV infusion rate is critical for patient safety. Nurses and medical professionals typically need to determine two main values: the Flow Rate (measured in milliliters per hour) and the Drip Rate (measured in drops per minute).
The IV Flow Rate Formula
To find the flow rate in mL/hr, use this simple formula:
Flow Rate (mL/hr) = Total Volume (mL) / Time (hours)
The IV Drip Rate Formula
When using manual gravity sets, you must calculate the drops per minute (gtt/min). This requires knowing the "Drop Factor," which is the number of drops the tubing produces for every 1 mL of fluid.
Drip Rate (gtt/min) = [Total Volume (mL) / Time (minutes)] × Drop Factor (gtt/mL)
Common Drop Factors
| Tubing Type | Standard Drop Factor |
|---|---|
| Macro-drip Set | 10, 15, or 20 gtt/mL |
| Micro-drip Set | 60 gtt/mL |
Practical Example
Scenario: A physician orders 1,000 mL of Normal Saline to be infused over 8 hours. The tubing drop factor is 15 gtt/mL.
- Step 1: Calculate mL/hr. 1,000 mL / 8 hours = 125 mL/hr.
- Step 2: Convert hours to minutes. 8 hours × 60 = 480 minutes.
- Step 3: Calculate gtt/min. (1,000 / 480) × 15 = 31.25, rounded to 31 gtt/min.