Infusion Rate Calculator
Work out infusion rate in mL/hour and drops per minute from volume and time — the standard IV drip rate calculation. Educational tool only.
Rates are calculated from the total volume and the exact time entered. In practice, a giving set delivers drops slightly unevenly, so the drip chamber is counted over a short interval, and electronic infusion devices are used wherever accuracy matters — for example with vasoactive drugs or in children.
Frequently asked questions
How do I calculate an infusion rate?
Divide the total volume in millilitres by the number of hours to get mL per hour. For a gravity drip, multiply volume by the giving set's drop factor and divide by the time in minutes to get drops per minute.
What is a drop factor?
The drop factor is the number of drops that make up one millilitre for a given giving set, printed on the packaging. Common values are 20 drops/mL for a standard adult set and 60 drops/mL for a paediatric micro-drop set.
Is this calculator safe to use for a patient?
No. It is an educational aid. Infusion calculations for real patients must be performed and independently checked according to your local policy.
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