Rex says
Same equations the textbooks use — just way less awkward. Pop in your stats and I'll tell you what the number actually means for you.
Try a scenario
Click to load — tweak from there.Inputs
Result
Pump rate (mL/hr)
125.0
Gravity rate (drops/min)
31
Seconds between drops
1.9
mL per minute
2.08
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One click, a permanent link with your numbers baked in.
How to use this
- 1Enter total volume (mL).
- 2Enter infusion time (hr).
- 3Enter tubing drop factor.
- 4Read your pump rate (ml/hr) on the right — it updates as you type.
- 5Hit Share to keep the scenario or send it to someone.
About this calculator
Convert an ordered volume and infusion time into a pump rate in mL per hour and a manual gravity rate in drops per minute for your tubing's drop factor.
Worked example
Using the values the calculator loads with:
Inputs
- Total volume: 1000 mL
- Infusion time: 8 hr
- Tubing drop factor: 15 gtt/mL (macro)
Results
- Pump rate (mL/hr): 125
- Gravity rate (drops/min): 31
- Seconds between drops: 1.9
- mL per minute: 2.08
What each field means
Inputs
- Total volume (mL)
- The total volume used in the calculation, measured in mL. Starts at 1000 mL so you have a working example on load.
- Infusion time (hr)
- The infusion time used in the calculation, measured in hr. Starts at 8 hr so you have a working example on load.
- Tubing drop factor
- Pick the option that matches your situation — the maths changes per option. Choices: 10 gtt/mL (macro), 15 gtt/mL (macro), 20 gtt/mL (macro), 60 gtt/mL (micro).
Results
- Pump rate (mL/hr)
- Returned as a decimal number and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Gravity rate (drops/min)
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Seconds between drops
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- mL per minute
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
Is this a substitute for clinical judgment?
No. It is an arithmetic aid for education and double-checking. Always follow your facility's protocol and verify against the physician order.
Macro or micro tubing?
Microdrip (60 gtt/mL) is used for small volumes and pediatric infusions where precision matters more than flow rate.
Accuracy and limitations
- Population formulas describe averages; individual bodies vary, especially at the extremes of height, age, or muscle mass.
- Results do not account for medical conditions, medication, or pregnancy.
- Use this as a directional reference, not a diagnosis — talk to a clinician before acting on it.
Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). IV Drip Rate Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/iv-drip-rate
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/iv-drip-rate" target="_blank" rel="noopener">IV Drip Rate Calculator — RevenueLab</a> (2026).</p>
Source: [IV Drip Rate Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/iv-drip-rate) (2026).