Drops per mL Converter

It depends on the bottle. A 2004 review found that eye-drop bottles deliver drops of 25 to 70 µL, which is about 14 to 40 drops per mL. The calculator uses 20 per mL (50 µL) as its main figure and shows the full range under the result, so a 5 mL bottle gives somewhere around 71 to 200 drops.

Macro-drip sets deliver 10, 15 or 20 drops per mL and micro-drip sets deliver 60, according to the Open RN Nursing Skills textbook. No single factor is standard across manufacturers, so check the factor on the set's packaging before calculating.

Less than you might think. A 1999 study of eye-drop solutions found that viscosity up to 25 mPa·s had no significant effect on drop weight under conditions like a patient's use. Surface tension mattered more: the lower it was, the lighter the drops. The angle the bottle was held at also changed drop weight.

For drops per minute, you also need the infusion time. Use the IV Drip Rate Calculator — it takes mL, time, and drop factor and returns drops/min directly. This converter just goes from mL ↔ drops without time.

A dropper can't deliver half a drop, so the result shows the whole-number count next to the exact decimal. When a prescription gives a dose in drops, follow the number on the prescription or label rather than converting it.