IV Drip Rate Calculator
10, 15, 20 gtt/mL are macrodrip sets; 60 gtt/mL is microdrip.
What is IV Drip Rate Calculator
An IV drip rate calculator works out how fast an intravenous infusion should run. It takes the volume to be infused, the total time, and the giving set's drop factor (gtt/mL), then returns the rate in drops per minute (gtt/min) for a gravity line and in mL/h for an infusion pump. The formula is drops per minute = (volume in mL times drop factor) divided by time in minutes.
How to use
- Enter the total volume to infuse in millilitres.
- Enter the infusion time and pick minutes or hours.
- Set the drop factor of your giving set, or tap a preset (10, 15, 20, 60 gtt/mL).
- Read the drip rate in gtt/min, plus the mL/h and seconds-per-drop values.
When to use it
Hanging 1000 mL of fluid over 8 hours with a 20 gtt/mL set? Enter those numbers and you get 42 gtt/min, or 125 mL/h on a pump. It saves the bedside arithmetic and gives you a second value to double-check the count you set on a gravity line.
Frequently asked questions
What is the formula for IV drip rate?
Drops per minute (gtt/min) = (volume in mL times drop factor in gtt/mL) divided by time in minutes. For example, 1000 mL over 480 minutes with a 20 gtt/mL set gives (1000 times 20) divided by 480, about 42 gtt/min.
What is the difference between macrodrip and microdrip?
Macrodrip sets deliver 10, 15, or 20 drops per mL and suit larger volumes and faster rates. Microdrip sets deliver 60 drops per mL and give finer control for small volumes, keep-vein-open rates, and paediatric infusions.
How do I set the drip rate on a gravity line?
Count the drops in the drip chamber for one minute (or use the seconds-per-drop value) and adjust the roller clamp until the count matches the calculated gtt/min. Recheck it periodically, since patient position and line height change the flow.
Can I share this tool with my inputs pre-filled?
Yes. The URL updates automatically as you type. Copy it from the address bar or use the Share button — anyone who opens the link will see your exact inputs ready to go.
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