Tirzepatide Dose Calculator
Turn your prescribed mg into exact units on a U-100 syringe.
Draw to
10units
Exact units
10.4u
Volume
0.104mL
Always verify against your vial and pharmacy label. Concentrations differ between products and batches — a vial reading 5 mg / 0.5 mL is 10 mg/mL, not 5. If your number here doesn't match what your prescriber told you, stop and call your pharmacy.
How to convert tirzepatide mg to syringe units
Compounded tirzepatide (the same molecule as Mounjaro and Zepbound) is drawn from a vial with an insulin syringe measured in units, where 100 units = 1 mL. To go from your prescribed milligrams to units you only need the vial's concentration:
units = (dose_mg ÷ concentration_mg/mL) × 100
The trap that causes overdoses
A vial label that reads “5 mg / 0.5 mL” is a 10 mg/mL concentration — not 5. Reading it as 5 would double your volume. This is the single most common compounding-math mistake, so the calculator asks for mg/mL explicitly and lets you derive it from a reconstituted vial if needed.
Frequently asked
- How many units is 5 mg of tirzepatide?
- It depends on the vial concentration. At 10 mg/mL, 5 mg = 50 units (0.5 mL). At 20 mg/mL, 5 mg = 25 units. Always enter your specific vial strength.
- What concentration is my tirzepatide vial?
- It is printed on the label as mg per mL, or as mg per a volume (e.g. 30 mg / 1.5 mL = 20 mg/mL). If your vial was reconstituted from powder, concentration = powder mg ÷ water mL.
- Is this the same for Mounjaro and Zepbound pens?
- No — branded Mounjaro and Zepbound auto-injector pens deliver a fixed dose and need no math. This calculator is for drawing compounded tirzepatide from a vial with a syringe.
Medical disclaimer. Tiro is a tracking companion, not a medical device, and nothing on this site is medical advice. Always follow the titration schedule and dosing instructions from your prescriber. Never change your dose without talking to them first.