Tirzepatide dosage calculator
To see the units to draw with a U-100 insulin syringe, enter the size of your Tirzepatide vial, the water you added and your dose.
This is reference information only. Your dose is set by your prescriber or by the product label; all we do here is convert it into units.
- Sizes of vials sold
- 10, 15, 20, 30, 40, 50, 60, 100, 120 mg
- status of approval
- FDA-approved
- a sample mix: 10 mg with 2 mL
- 5 mg per mL
Working out the Tirzepatide math
To find the strength, divide the amount in the vial by the water. In a vial, 10 mg mixed with 2 mL of water gives 5 mg in each mL. Take your dose and divide it by that strength for mL; multiply the result by 100 for the units on a U-100 syringe.
That means 2.5 mg from that vial works out to 0.5 mL, or 50 units.
A quick look at Tirzepatide units
| Your dose | 10 mg vial + 2 mL | 15 mg vial + 3 mL | 20 mg vial + 2 mL | 30 mg vial + 3 mL | 40 mg vial + 2 mL |
|---|---|---|---|---|---|
| 2.5 mg | 50 units | 50 units | 25 units | 25 units | 12.5 units |
| 5 mg | 100 units | 100 units | 50 units | 50 units | 25 units |
| 7.5 mg | 150 units over 1 mL | 150 units over 1 mL | 75 units | 75 units | 37.5 units |
| 10 mg | 200 units over 1 mL | 200 units over 1 mL | 100 units | 100 units | 50 units |
| 12.5 mg | 250 units over 1 mL | 250 units over 1 mL | 125 units over 1 mL | 125 units over 1 mL | 62.5 units |
| 15 mg | 300 units over 1 mL | 300 units over 1 mL | 150 units over 1 mL | 150 units over 1 mL | 75 units |
Each cell shows, for a U-100 syringe, the line to draw to for the vial and water listed.
Label doses for Tirzepatide in units
The FDA label supplies every dose step used in these tables: Zepbound label on DailyMed and Mounjaro label on DailyMed. Each step is then changed to units for compounded or research vials. Which step belongs to you is decided by your prescriber.
Zepbound (given under the skin, once a week)
| Label step | Dose | 10 mg + 2 mL | 15 mg + 3 mL | 20 mg + 2 mL |
|---|---|---|---|---|
| Weeks 1-4 | 2.5 mg | 50 units | 50 units | 25 units |
| Then, after at least 4 weeks on each step | 5 mg | 100 units | 100 units | 50 units |
| Next step | 7.5 mg | 150 units over 1 mL | 150 units over 1 mL | 75 units |
| Next step | 10 mg | 200 units over 1 mL | 200 units over 1 mL | 100 units |
| Next step | 12.5 mg | 250 units over 1 mL | 250 units over 1 mL | 125 units over 1 mL |
| Highest step | 15 mg | 300 units over 1 mL | 300 units over 1 mL | 150 units over 1 mL |
Mounjaro (given under the skin, once a week)
| Label step | Dose | 10 mg + 2 mL | 15 mg + 3 mL | 20 mg + 2 mL |
|---|---|---|---|---|
| Weeks 1-4 | 2.5 mg | 50 units | 50 units | 25 units |
| Then | 5 mg | 100 units | 100 units | 50 units |
| After at least 4 weeks, raise in 2.5 mg steps if needed | 7.5 mg | 150 units over 1 mL | 150 units over 1 mL | 75 units |
| Next step | 10 mg | 200 units over 1 mL | 200 units over 1 mL | 100 units |
| Next step | 12.5 mg | 250 units over 1 mL | 250 units over 1 mL | 125 units over 1 mL |
| Highest step | 15 mg | 300 units over 1 mL | 300 units over 1 mL | 150 units over 1 mL |
Has Tirzepatide been FDA-approved?
Lilly's prefilled pens and vials are FDA-approved as Mounjaro and Zepbound; compounded and research vials don't have FDA approval. Only label steps from the FDA label are shown here; for any other vial, your prescriber sets the dose.
Frequently asked questions
For a 10 mg Tirzepatide vial, how much water do I add?
How much water you use is up to you; the amount only affects how strong each mL is. 2 mL gives 5 mg per mL; adding more water means each unit holds less, so small doses are easier to measure.
How many units does 1 mg of Tirzepatide equal?
That depends on how strong your mix is. At 5 mg/mL, 1 mg comes to 20 units. Put your vial and water into the calculator and your number appears.
How long does mixed Tirzepatide last?
Your product or prescription lists a storage line, and you should follow it. Per CDC guidance, you should use bacteriostatic water itself within 28 days of that first needle.