Universal dosage calculator
Nursing math helper for dose-to-volume, weight-based dosing, and IV drip rate practice.
Educational use only. This tool is for practice and double-checking math. Always follow your facility protocols, provider orders, and approved clinical references.
1. Dose to volume (mL to give)
Ordered dose
e.g., 250 mg
Stock amount
e.g., 500 mg
Stock volume (mL)
e.g., 5 mL
mL to give:
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Formula: mL to give = (Ordered dose ÷ Stock amount) × Stock volume.
2. Weight-based dose (mg/kg)
Dose ordered
mg per kg
Patient weight
Weight unit
Total dose:
—
If weight is in pounds, it is converted to kilograms using 1 kg ≈ 2.20462 lb.
3. IV rate and drops per minute
Total volume (mL)
Time
Time unit
Drop factor (gtt/mL)
For gravity tubing (optional)
Rate (mL/hr):
—
Drip rate (gtt/min):
—
mL/hr = Total volume ÷ Time (hr).
gtt/min = (Total volume × Drop factor) ÷ Time (min).