IV Infusion Time Calculator
Written by George Lambroglou, RN • Last reviewed 21 Jun 2026
Calculate how long an IV infusion will take to finish. Enter the remaining volume in mL and the infusion rate in mL/hr.
Formula
Time (hours) = Volume (mL) ÷ Rate (mL/hr)
Worked Example
500 mL remaining at 125 mL/hr. How long until finished?
Time = 500 ÷ 125 = 4.0 hours = 4h 0m
Answer: 4 hours 0 minutes
Note: Use the actual remaining volume in the bag, not the original bag size, for an accurate finish time.