Free IV therapy tool
IV drip rate calculator
Calculate drops per minute (gtt/min) for gravity tubing: choose the drop factor, enter the volume and time, and get the whole-drop answer plus the mL/hr pump rate — with the full worked setup behind every result. Free, no signup, runs in your browser.
Interactive calculator
IV drip rate calculator
Enter the volume, the time, and the tubing’s drop factor, and read the drops-per-minute answer with its worked setup below. The pump rate in mL/hr is shown too, as a cross-check. Results update as you type.
Result
Enter the volume, time, and drop factor to see the answer and the worked setup.
For education and practice only. This tool is a study aid, not a substitute for clinical judgment, the pump, or institutional policy. Always independently verify an infusion rate before administering anything to a patient.
How it works
The drops-per-minute formula
The drop factor converts milliliters into drops, and dividing by the total minutes spreads those drops evenly across the infusion. Set it up with dimensional analysis so the units you do not want cancel and gtt/min is left.
IV drip rate (gtt/min)
gtt/min = (Volume mL × drop factor gtt/mL) ÷ Time (min)
For gravity tubing counted by drops. The drop factor is printed on the tubing package — 10, 15, or 20 for macrodrip, 60 for microdrip. Drops are whole, so round the answer to a whole number.
IV flow rate (mL/hr)
Rate (mL/hr) = Volume (mL) ÷ Time (hr)
Programs a volumetric pump and is the everyday IV calculation. This tool shows it alongside gtt/min as a cross-check — with a 60 gtt/mL microdrip set the two values are equal.
Worked example
A drip rate, step by step
The order
Infuse 1,000 mL over 8 hours using gravity tubing with a drop factor of 15 gtt/mL. What is the drip rate in gtt/min?
The setup
- 1. Time to minutes: 8 hr × 60 = 480 min.
- 2. gtt/min = (1,000 mL × 15 gtt/mL) ÷ 480 min.
- 3. = 15,000 ÷ 480 = 31.25 gtt/min.
- 4. Round to whole drops → 31 gtt/min.
Answer: 31 gtt/min (pump cross-check: 1,000 ÷ 8 = 125 mL/hr).
Why it works
The units cancel cleanly: mL × (gtt/mL) leaves gtt, and dividing by minutes gives gtt/min. Because you can only count whole drops, 31.25 rounds to 31 gtt/min — round only at this final step.
Enter the same numbers in the calculator above and you will see this exact worked setup returned, along with the 125 mL/hr pump rate.
Tip: with microdrip tubing (60 gtt/mL) the gtt/min always equals the mL/hr rate — a fast sanity check at the bedside.
Common questions
IV drip rate, explained
- How do I calculate IV drip rate in gtt/min?
- Multiply the volume in milliliters by the tubing's drop factor in gtt/mL, then divide by the time in minutes: gtt/min = (mL × drop factor) ÷ minutes. If the order gives the time in hours, convert to minutes first (hours × 60). Because you count whole drops, round the answer to a whole number.
- What is a drop factor and where do I find it?
- The drop factor is the number of drops per milliliter a particular IV tubing set delivers, and it is printed on the tubing package. Macrodrip sets are typically 10, 15, or 20 gtt/mL; microdrip (pediatric) tubing is 60 gtt/mL. Choose the value that matches the set you are using.
- What is the difference between gtt/min and mL/hr?
- mL/hr is the volumetric rate a pump is programmed to, calculated as volume ÷ time in hours. gtt/min is the count of drops per minute for gravity tubing, which depends on the drop factor. This tool shows both: the gtt/min answer and the mL/hr rate as a cross-check.
- Why does the drop rate equal the mL/hr with microdrip tubing?
- Microdrip tubing delivers 60 gtt/mL, and there are 60 minutes in an hour. The two 60s cancel in the formula, so gtt/min comes out equal to mL/hr. That makes it a quick sanity check whenever you use a 60 gtt/mL set.
- Should I round the drip rate up or down?
- Round to the nearest whole drop, because you cannot count a fraction of a drop. A value of 31.25 rounds to 31 gtt/min and 31.5 rounds to 32 gtt/min. Keep full precision through the calculation and round only at the final step.
- Is this IV drip rate calculator free and mobile-friendly?
- Yes. It is completely free, needs no account, and runs entirely in your browser, so it works on a phone. It is a study and practice aid only — always verify a real infusion against the order, the pump, and institutional policy before administering.
Turn the method into a reflex
Study the method, then drill the problems
This calculator does the arithmetic; getting fast and safe takes repetition. Use the all-in-one dosage calculator for oral and weight-based modes, read the dosage study guide for the full method, then practice fill-in problems or sit a full mixed exam.
This calculator and all study material on this site are provided for practice and study only — they are not medical advice or a substitute for clinical judgment, the pump, or institutional policy. Verify every infusion before administering. NCLEX® is a registered trademark of the National Council of State Boards of Nursing, Inc. (NCSBN), which does not endorse or sponsor this site.