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IV Infusion Time & Volume Calculator

IV infusion time & volume calculator allows you to calculate total infusion time & volume, remaining infusion time & volume of a given infusion rate.

Infusion Time Calculator

This Infusion Time calculator helps to determine the correct time needed to administer the given volume  — based on the volume and infusion rate.

Infusion Volume Calculator

This IV infusion volume calculator helps to determine the correct volume needed to administer in given time — based on the time and infusion rate.

IV Infusion Time & Volume Calculator

IV Infusion Time Formulas

IV infusion time & volume Calculator

IV Infusion Volume Formulas

IV infusion time calculation

Example 1:

Using a volumetric IV pump calculate to duration of 1000 milliliters (mL) of normal saline infusing at 125 milliliters/hour (mL/hr).

  • Volume = 1000 mL
  • Rate = 125 mL
1000 mL/125 mL

The answer is 8 hours.

Example 2: 

There are 250 mL of D5W infusing at 33 (gtt/min) on IV tubing calibrated at 10 drops/milliliter (gtt/mL).  Calculate the infusion time.

  • Volume = 250 mL
  • IV tubing calibration = 10 gtt/mL
  • gtt/min = 33 gtt/min
(250 mL×10)/(33×60 min)

The answer is 1.26 hours.

IV infusion volume calculation

Example 1: 

There are ? mL of D5W infusing at 50 (gtt/min) on IV tubing calibrated at 15 drops/milliliter (gtt/mL) in 1hr 40 minutes.  

  • Time = 60+40 =100min
  • IV tubing calibration = 20 gtt/mL
  • gtt/min = 50 gtt/min
vol.= (100 x 50)/20

The answer is 500 ml.

General Tips

  • Check that your answer makes sense clinically.
  • Triple check your work.
  • Have a colleague or pharmacist check your work.
  • Know general therapeutic drug doses for commonly administered medications.

Drop Factor

Drop factor is the number of drops it takes to equal 1 ml with a specific type of IV

The drop factor is stated on the tubing package.

Macrodrip: 10, 15 and 20 gtts/minute

Microdrip: 60 gtts/minute

How to use IV infusion time and volume Calculator

  • Select what you want to find out time or volume.
  • Tick IV Pump or No IV Pump.
  • Enter infusion flow rate & total fluid volume
  • Click on calculate to find out

Infusion time or volume

Note: In case of no IV Pump you need to select drop factor (IV tubing calibration usally mentioned on IV set)

Click Here to calculate maintenance fluid.