IV drip rate & flow rate reference
How this calculator works
The calculator converts a prescribed volume and infusion time into a
gravity-drip rate in drops per minute, using the drop factor printed on the
IV tubing. The governing relationship is:
gtt/min = (total volume mL × drop factor gtt/mL) ÷ time in minutes
Worked example: 1200 mL ordered over 6 hours with 10 gtt/mL macrodrip tubing.
Six hours is 360 minutes, so the rate is (1200 × 10) ÷ 360 =
33 gtt/min.
Drop factor: macrodrip vs microdrip
The drop factor is the number of drops the tubing delivers per
milliliter, and it is printed on the administration-set packaging.
Macrodrip sets deliver larger drops at 10, 15, or 20 gtt/mL and
suit routine or higher-volume infusions. Microdrip sets deliver
fine drops at 60 gtt/mL and suit small volumes, pediatric doses, or rates that
need tighter control. Using the wrong drop factor in the formula changes the
calculated rate substantially, so always read it from the actual set.
Drip rate (gtt/min) vs flow rate (mL/hr)
Flow rate is volume per hour (mL/hr) and is what an electronic
infusion pump is programmed with. Drip rate is drops per minute
(gtt/min) and is what you count when running an infusion by gravity without a
pump. They describe the same infusion: flow rate = total volume ÷ time in
hours, and gtt/min = (mL/hr × drop factor) ÷ 60. This tool shows both
and includes a converter between them.
Rounding to whole drops
You can only count whole drops, so clinical practice rounds the drip rate to the
nearest whole gtt/min. The calculator rounds by default and can also display the
exact unrounded value for checking. The mL/hr converter and flow-rate figures use
exact arithmetic; only the final drops-per-minute figure is rounded.
Gravity drip vs infusion pump
A gravity setup is regulated with a roller clamp and verified by counting drops in
the drip chamber against the calculated gtt/min. An infusion pump is set directly
in mL/hr and does not require a drop count. This calculator targets the gravity
method but reports the mL/hr equivalent so it is useful with either approach.
Data handling and privacy
Calculations run entirely in your browser. Nothing you enter is transmitted or
stored.
Scope & safety
PepRecon is a research and education resource. This calculator and reference
material are provided for informational purposes only, are not medical advice, and
do not establish an infusion order. Drug and fluid administration must follow a
qualified clinician's prescription and your institution's protocols; always verify
the rate against the order and the actual tubing.