Free calculator
Enter the volume and the infusion time to get the pump rate in mL/hr. See the mL/hr formula for the method.
Pump rate
An IV pump is set in milliliters per hour, so the rate is simply the total volume divided by the total time in hours:
Flow rate (mL/hr) = volume (mL) ÷ time (hr)
The result is rounded to a whole mL/hr because that is what most pumps accept. The full method, with practice problems, is in the IV flow rate lesson.
An order reads: infuse 1000 mL of 0.9% normal saline over 8 hours using an IV pump. What rate should the pump be set to?
Flow rate (mL/hr) = total volume (mL) divided by time (hours). For example, 1000 mL over 8 hours is 1000 / 8 = 125 mL/hr.
Most IV pumps are programmed in whole mL/hr, so the calculated rate is rounded to the nearest whole number. Follow your facility's policy for pumps that accept decimal rates.
Convert minutes to hours first by dividing by 60 (for example, 30 min = 0.5 hr). This calculator does that conversion for you when you choose minutes.