Infusion Pump Rate calculator
The infusion pump rate calculator converts a total volume and an infusion time into millilitres per hour — the number you programme into a volumetric pump. Enter the volume in millilitres and the time in hours and it returns the mL/hr rate.
The formula
Rate (mL/hr) = volume (mL) / time (hr). Unlike a gravity set, no drop factor is involved: the pump controls delivery, so tubing does not change the number.
A worked example
An order for 1000 mL over 8 hours is 1000 / 8 = 125 mL/hr. For a time given in minutes, convert first: 250 mL over 45 minutes is 0.75 hours, so 250 / 0.75 = 333.3 mL/hr.
Sanity check
Rates above 1000 mL/hr are flagged, since that usually means minutes were entered where hours were expected. A genuinely high rate can be correct in resuscitation — the warning asks you to look, not to stop.
What this does not do
This gives a rate only. It does not check the fluid, the order, line compatibility or your pump library limits, and it is not the calculator for weight-based mcg/kg/min infusions. Every result is a check on your arithmetic, not a clinical decision. Confirm the order, the concentration on the label and your own policy before administering anything.
Frequently asked questions
My order is in minutes — what do I enter?
Convert to hours first: divide the minutes by 60. Ninety minutes is 1.5 hours.
Does the tubing drop factor matter here?
No. Drop factor only matters for gravity infusions counted in gtt/min. A pump delivers by volume.
Can I use this for a vasopressor drip?
No. A mcg/kg/min order needs the weight-based infusion calculator, which accounts for weight and bag concentration.
By The Nursana team · Last updated · Canonical: https://nursana.aoneahsan.com/tools/infusion-rate
Nursana provides reference tools only and does not give medical, legal or tax advice.