Tirzepatide dosage calculator
Tirzepatide is FDA-approved as Mounjaro and Zepbound, supplied in single-dose pens and vials of a fixed strength. Compounded and research-grade tirzepatide is instead sold as multi-milligram vials that have to be reconstituted, and the units drawn depend entirely on how much water was added. The calculator converts any vial, water volume and amount; the tables show the labelled dose steps at a common concentration.
Full research profile: Tirzepatide. For any other concentration, use the insulin syringe units converter.
For research use only. Not medical advice. This page does arithmetic; it does not recommend an amount.
Tirzepatide reconstitution chart
Concentration and micrograms per mark on a U-100 insulin syringe, by vial size and water added. The peptide amount never changes; only how concentrated it is.
| Vial | + 1 mL water | + 2 mL water | + 3 mL water |
|---|---|---|---|
| 10 mg | 10 mg/mL · 100 mcg per unit | 5 mg/mL · 50 mcg per unit | 3.33 mg/mL · 33.3 mcg per unit |
| 15 mg | 15 mg/mL · 150 mcg per unit | 7.5 mg/mL · 75 mcg per unit | 5 mg/mL · 50 mcg per unit |
| 30 mg | 30 mg/mL · 300 mcg per unit | 15 mg/mL · 150 mcg per unit | 10 mg/mL · 100 mcg per unit |
| 60 mg | 60 mg/mL · 600 mcg per unit | 30 mg/mL · 300 mcg per unit | 20 mg/mL · 200 mcg per unit |
Most-listed Tirzepatide vial sizes across vendors we track: 10 mg (20 vendors), 30 mg (16 vendors), 60 mg (12 vendors), 20 mg (11 vendors). Compare prices.
Tirzepatide doses from the label and trials, in syringe units
The doses reported in each cited source, converted to U-100 syringe units at common vial and water combinations. This is arithmetic on the cited figures, not a recommendation; a dash means the amount is more than one full 1 mL syringe at that concentration.
Mounjaro label: 2.5 mg start, escalated in 2.5 mg steps to 15 mg, once weekly
| Dose | 10 mg + 2 mL (5 mg/mL) | 30 mg + 3 mL (10 mg/mL) | 60 mg + 3 mL (20 mg/mL) |
|---|---|---|---|
| 2.5 mg | 50 units (0.5 mL) | 25 units (0.25 mL) | 12.5 units (0.125 mL) |
| 5 mg | 100 units (1 mL) | 50 units (0.5 mL) | 25 units (0.25 mL) |
| 7.5 mg | — | 75 units (0.75 mL) | 37.5 units (0.375 mL) |
| 10 mg | — | 100 units (1 mL) | 50 units (0.5 mL) |
| 12.5 mg | — | — | 62.5 units (0.625 mL) |
| 15 mg | — | — | 75 units (0.75 mL) |
Source: MOUNJARO (tirzepatide) prescribing information, DailyMed
Common questions
How many units is 2.5 mg of Tirzepatide?
It depends on the concentration. In a 10 mg vial mixed with 2 mL of bacteriostatic water (5 mg/mL), 2.5 mg is 0.5 mL, or 50 units on a U-100 insulin syringe. With 3 mL of water instead, the same 2.5 mg is 75 units.
How much bacteriostatic water do you add to a 10 mg Tirzepatide vial?
There is no single correct volume: the amount of peptide is fixed and the water only sets the concentration. For 10 mg, 1 mL gives 10 mg/mL (100 mcg per unit), 2 mL gives 5 mg/mL (50 mcg per unit) and 3 mL gives 3.33 mg/mL (33.3 mcg per unit). More water makes each syringe mark hold less, which makes small amounts easier to measure accurately.
Are the Tirzepatide doses on this page recommendations?
No. They are the doses reported in the cited source (MOUNJARO (tirzepatide) prescribing information, DailyMed), converted to syringe units as arithmetic. Approved products come in their own strengths and devices, and what any person should use is a decision for a licensed clinician.
What does one unit on an insulin syringe mean?
A unit is a volume mark, not an amount of drug. On a U-100 syringe 100 units fill 1 mL, so 10 units is always 0.1 mL; how much peptide those 10 units hold depends only on the concentration you mixed. U-40 syringes use 40 marks per mL, so the same volume reads as a different number of units.