Free tool

IV drip rate calculator.

Enter volume, time, and drop factor. Get gtt/min instantly.

Macrodrip: 10 / 15 / 20 gtt/mL. Microdrip: 60 gtt/mL (pediatrics, precise infusions).

Result

125 gtt/min

Formula: (500 mL × 15 gtt/mL) ÷ 60 min

Worked example

Order: 1000 mL NS over 8 hours with 15 gtt/mL tubing. Time = 8 × 60 = 480 min. Rate = (1000 × 15) ÷ 480 = 31 gtt/min.

FAQ

What is the drip rate formula?

gtt/min = (Volume in mL × Drop factor in gtt/mL) ÷ Time in minutes. Match the drop factor to the tubing label on the package.

What tubing drop factors are common?

Macrodrip: 10, 15, or 20 gtt/mL for maintenance and boluses. Microdrip: 60 gtt/mL for pediatrics and precise infusions.

How do I convert hours to minutes?

Multiply hours by 60. A 250 mL infusion over 2 hours runs over 120 minutes.

Do I round drops per minute?

Yes — you can't count fractional drops. Round to the nearest whole number and confirm by counting drops for 15 seconds ×4.