IV Drip Rate & Infusion Calculator
Calculate mL/hr and Drops per Minute (gtt/min) for intravenous fluids.
10 (Macro-drip)
15 (Macro-drip)
20 (Standard)
60 (Micro-drip)
Infusion Rate: 0 mL/hr
Drip Rate: 0 gtt/min (drops/min)
Total Time: 0 minutes
How to Calculate IV Drip Rates (mL/hr)
In clinical settings, calculating the correct IV infusion rate is critical for patient safety. This calculator helps healthcare professionals determine both the electronic pump setting (mL/hr) and the manual gravity drip rate (gtt/min).
The mL/hr Formula
When using an infusion pump, you simply need the total volume and the time in hours. The formula is:
Infusion Rate (mL/hr) = Total Volume (mL) ÷ Total Time (hr)
The Drip Rate (gtt/min) Formula
If an infusion pump is unavailable and you are using gravity, you must calculate the drops per minute based on the tubing's drop factor. The formula is:
Drip Rate (gtt/min) = [Volume (mL) × Drop Factor (gtt/mL)] ÷ Time (minutes)
Understanding Drop Factors
| Tubing Type | Drop Factor (gtt/mL) | Common Use |
|---|---|---|
| Macro-drip | 10, 15, or 20 | Routine adult fluid replacement |
| Micro-drip | 60 | Pediatrics or high-potency medications |
Example Calculation
Scenario: A physician orders 1,000 mL of Normal Saline to be infused over 8 hours using a standard 15 gtt/mL drip set.
- Step 1 (mL/hr): 1,000 mL ÷ 8 hours = 125 mL/hr
- Step 2 (Total Minutes): 8 hours × 60 = 480 minutes
- Step 3 (gtt/min): (1,000 mL × 15) ÷ 480 minutes = 31.25 (approx 31) gtt/min
Clinical Best Practices
Always double-check calculations with a colleague, especially when administering high-alert medications like potassium, insulin, or heparin. Ensure the infusion pump settings match your manual calculation to verify equipment accuracy.