IV Infusion Rate Calculator

What is IV Infusion Rate Calculator?

An IV Infusion Rate Calculator helps clinicians and students translate medication orders into practical pump settings (mL/hr) or gravity drip rates (gtt/min). It accepts common order formats—volume over time, mg/hr, mcg/kg/min—and uses the bag concentration and infusion set’s drop factor to return a safe, auditable rate. By displaying each substitution and unit conversion in responsive formula blocks, it clarifies how dose, weight, concentration, and time interact, reducing arithmetic errors in high‑stakes situations. This tool is educational support only; always follow institutional protocols and drug‑specific guidance.

About the IV Infusion Rate Calculator

The calculator supports weight‑based drips (mcg/kg/min), fixed doses (mg/hr), and simple volume‑time infusions. It handles unit conversions (mcg⇄mg, min⇄hr), computes gravity drip rates from any drop factor (10, 15, 20, or microdrip 60 gtt/mL), and rounds results appropriately for pumps or manual counting. Each step is transparent: it shows the concentration from the prepared bag, converts the ordered dose to a per‑hour equivalent, and divides by concentration to yield mL/hr. For gravity infusions, it multiplies by the drop factor and divides by 60 to obtain gtt/min.

How to Use this IV Infusion Rate Calculator

Select the order type: volume over time, mg/hr, or mcg/kg/min (enter patient weight if applicable).
Enter bag concentration (drug amount and diluent volume) to compute mg/mL.
Optionally enter a drop factor to get gravity gtt/min; otherwise you’ll receive mL/hr for pumps.
Click calculate to see substitutions, unit conversions, and the final rate with suggested rounding.
Verify against your protocol and medication monograph before administration.

Examples

Example 1: Volume over time with gravity set

Infuse \(1000\,\mathrm{mL}\) over \(8\,\mathrm{hr}\) using a \(20\,\mathrm{gtt/mL}\) set.

Example 2: Weight‑based drip (mcg/kg/min)

Order: \(5\,\mathrm{mcg/kg/min}\); weight \(70\,\mathrm{kg}\). Bag: \(400\,\mathrm{mg}\) in \(250\,\mathrm{mL}\Rightarrow 1.6\,\mathrm{mg/mL}\).

Example 3: Fixed mg/hr order

Order: \(12\,\mathrm{mg/hr}\). Solution: \(2\,\mathrm{mg/mL}\).

Example 4: Time required at a given pump rate

Volume \(=250\,\mathrm{mL}\), pump \(=50\,\mathrm{mL/hr}\).

FAQs

What’s the difference between mL/hr and gtt/min?

mL/hr is a pump setting. gtt/min is for gravity sets and depends on the tubing drop factor (gtt/mL).

How do I find the drop factor?

It’s printed on the IV tubing package (e.g., 10, 15, 20, or 60 gtt/mL for microdrip).

Can I round the drip rate?

Yes—gravity counts must be whole drops. Round to the nearest whole gtt/min while staying within protocol.

What if my order is in mcg/kg/hr?

Convert to mcg/kg/min by dividing by 60, or compute mg/hr directly, then divide by concentration.

Does concentration change if I adjust diluent volume?

Yes. Recalculate mg/mL whenever the bag volume or drug amount changes.

Is a microdrip set always 60 gtt/mL?

Commonly yes, but confirm on the package; never assume.

Can this replace my institution’s policies?

No. Use it as a learning and double‑check aid; follow local protocols and drug references.

How are units handled?

The tool converts mcg↔mg and min↔hr automatically; review the shown conversions before use.

What if the patient’s weight changes?

Weight‑based drips should be recalculated with the current verified weight.

Why is my pump rate different from the gravity rate?

Gravity depends on drop factor; pumps deliver directly in mL/hr, independent of tubing.

How do I check my math quickly?

Estimate: larger dose or concentration ↓ mL/hr? Concentration in denominator means higher concentration requires fewer mL/hr.