IV drip rate calculator

Updated October 13, 2026 by madebykamal

To find an IV drip rate in drops per minute, multiply the volume in mL by the drop factor of the tubing in gtt/mL and divide by the time in minutes: gtt/min = mL × gtt/mL ÷ minutes. For 1,000 mL over 8 hours on 15 gtt/mL tubing, that is 1,000 × 15 ÷ 480 = 31.25, which rounds to 31 drops a minute, and the same order runs at 125 mL/hr on a pump. Enter your order below for the drip rate, the pump rate and the time to infuse, with the formula filled in with your numbers.

General information, not medical advice. How these guides are made.

How to calculate drops per minute (gtt/min)

Gravity tubing runs in drops per minute: the rate is set with the roller clamp while watching the drops fall into the drip chamber. Georgia Highlands College's clinical calculations module works 1,000 mL over 9 hours on 20 gtt/mL tubing as 1,000 × 20 ÷ 540 = 37.04, or 37 gtt/min. The steps:

• Take the volume to infuse, in mL, from the order.
• Turn the time into minutes: multiply the hours by 60 and add any minutes, so 8 hours is 480 minutes.
• Read the drop factor, in gtt/mL, from the tubing package.
• Multiply the volume by the drop factor and divide by the minutes.
• Round to a whole drop: 37.04 becomes 37 gtt/min.

ChartKey: Medical Keyboard

Keyboard for medical charting

Get it on the App StoreAbout the app

On a computer? Scan this with your iPhone camera to open it in the App Store.

mL/hr or gtt/min: pump or gravity

A pump is programmed in milliliters per hour. OpenStax's Clinical Nursing Skills says all IV pumps regulate the rate in mL/hr, and that electronic pump infusion is recommended in all settings to reduce infusion-related medication errors. The FDA describes an infusion pump as a device that delivers fluids in controlled amounts, with a trained user programming the rate and duration. The pump rate is the volume divided by the hours: 1,000 mL over 8 hours is 125 mL/hr.

Without a pump, the same order becomes a drop count: gtt/min = mL/hr × gtt/mL ÷ 60. Georgia Highlands College's module gives 125 mL/hr on 15 gtt/mL tubing as 31 gtt/min, and rounds pump rates to a whole mL/hr. To see how long a bag will run, divide the volume by the mL/hr and give the answer in hours and minutes: 500 mL at 75 mL/hr is 6.667 hours, or 6 hours 40 minutes.

Macrodrip and microdrip drop factors

The drop factor is how many drops a set delivers per milliliter, written gtt/mL. OpenStax's Clinical Nursing Skills says it is located on the packaging of the IV tubing and is important to verify when calculating rates.

Sets are made in each size. B. Braun, for one, sells 10, 15, 20 and 60 drop gravity sets and states the drops per mL for each product, so read the package of the set in your hand rather than assuming a number. If it shows a figure that is not in the calculator's list, choose Another number and type it. The two kinds, as OpenStax describes them:

• Macrodrip: 10, 15 or 20 gtt/mL, used for routine primary infusions for adults.
• Microdrip: 60 gtt/mL, used in pediatric or neonatal care where small amounts of fluid run over a longer time.

The 60 gtt/mL shortcut

On microdrip tubing, the drops per minute equal the mL per hour. The formula becomes mL/hr × 60 ÷ 60, and the two 60s cancel: 60 drops make a milliliter and 60 minutes make an hour. So 125 mL/hr runs at 125 gtt/min on a 60 gtt/mL set, and 50 mL/hr at 50 gtt/min.

The same idea gives a quick check for macrodrip sets. Divide the mL/hr by 6 for 10 gtt/mL tubing, by 4 for 15 gtt/mL and by 3 for 20 gtt/mL: 125 mL/hr is about 21, 31 and 42 gtt/min. The chart in the calculator lists common rates worked out this way.

Rounding and checking your answer

Drops are counted whole. OpenStax's Pharmacology for Nurses says a calculation for drops is rounded to the nearest whole number because it is not possible to give a partial drop, and Georgia Highlands College rounds one half up: 34.5 becomes 35 gtt/min and 38.4 becomes 38. The calculator rounds only the final answer and shows the figure before rounding.

To check a running line, OpenStax suggests counting the drops in the drip chamber for one full minute, or dividing the gtt/min by four for the drops in 15 seconds: 19 gtt/min is about 5 drops every 15 seconds. It also suggests counting again regularly, for example every one to two hours or after the tubing is bumped. Pharmacology for Nurses adds that rounding rules may change in pediatric settings and with high-alert medications, so follow your institution's policy.

Drip rates inside ChartKey

ChartKey: Medical Keyboard is a medical charting keyboard for iPhone and iPad. With ChartKey Pro, an IV drip rate calculator sits inside the keyboard, alongside dose by weight, corrected calcium and BMI calculators. The keyboard autocorrects drug names, leaves clinical abbreviations such as q4h as you typed them, and expands dot phrases such as .sbar into a full SBAR handoff report with fill-in fields. ChartKey is a typing tool, not a clinical reference or decision-support system, so confirm clinical content against your institution's approved sources.

What this calculator does not do

It does arithmetic only. It does not check whether an order, a volume or a rate is right for a patient, and it is not medical advice. The provider's order, the pump in use and your facility's policy govern what is given. Nothing you type is sent anywhere: the calculator runs in your browser.

Questions people ask

Related

• SBAR Example for Nursing Handoff, With a Template
• Joint Commission Do Not Use List of Abbreviations
• What Is a Dot Phrase? Meaning and Charting Examples
• Common Medical Abbreviations for Nurses, by Use
• ChartKey: Medical Keyboard