Tirzepatide dosage calculator

Enter the amount in your tirzepatide vial, its total solution volume and the dose your prescriber supplied. The calculator converts those numbers into mL and U-100 syringe units. It does not set a dose or choose a mixing volume.

Converts a dose you already have; it does not recommend one. How we check our work Sources

How the math works

concentration (mg/mL) = mg in the vial ÷ total solution (mL) volume to draw (mL) = dose (mg) ÷ concentration units (U-100) = volume (mL) × 100

Tirzepatide doses are usually written in milligrams. The same 5 mg dose can be 25 units from one vial and 100 units from another, which is why a number of units means nothing without the vial size and the volume.

Conversion tables by vial amount

Find the vial in the rows and the total solution in the columns. Multiply the second table's number by your dose in mg: 5 mg from a 20 mg vial with 2 mL is 5 × 10 = 50 units.

Tirzepatide powder vials: concentration in mg/mL, by total solution volume
Vial	1 mL	1.5 mL	2 mL	2.5 mL	3 mL
5 mg	5	3.333	2.5	2	1.667
10 mg	10	6.667	5	4	3.333
15 mg	15	10	7.5	6	5
20 mg	20	13.333	10	8	6.667
30 mg	30	20	15	12	10
40 mg	40	26.667	20	16	13.333
60 mg	60	40	30	24	20

Tirzepatide powder vials: U-100 units for each 1 mg, by total solution volume
Vial	1 mL	1.5 mL	2 mL	2.5 mL	3 mL
5 mg	20	30	40	50	60
10 mg	10	15	20	25	30
15 mg	6.67	10	13.33	16.67	20
20 mg	5	7.5	10	12.5	15
30 mg	3.33	5	6.67	8.33	10
40 mg	2.5	3.75	5	6.25	7.5
60 mg	1.67	2.5	3.33	4.17	5

Values are rounded for display; the calculator works from the unrounded numbers. Volumes assume the total solution equals the water added, which is a close approximation.

Worked examples

These show arithmetic only, not suggested doses or dilutions.

10 mg vial, 2 mL total (5 mg/mL): 2.5 mg = 0.5 mL = 50 units
30 mg vial, 3 mL total (10 mg/mL): 7.5 mg = 0.75 mL = 75 units
60 mg vial, 3 mL total (20 mg/mL): 15 mg = 0.75 mL = 75 units

Identify the product before using the calculator

Approved tirzepatide products are supplied as solutions. A powder requiring reconstitution is not the same presentation. This calculator cannot establish the identity, quality or suitability of a vial.

For a ready-to-use product, use its labeled administration instructions. For a pharmacy-dispensed vial, use the concentration and dose on its own label; ask the pharmacy if either is unclear. Do not substitute a unit count from a different vial.

Correction — November 9, 2026. The page previously described the calculator primarily as a powder-vial tool and incompletely listed approved presentations. It now explains liquid-vial inputs and links to presentation-specific labeling.

Questions

Do approved tirzepatide products need reconstitution?

Zepbound and Mounjaro are supplied as solutions, not powder to mix. Presentations differ; current Zepbound labeling includes single-dose pens and vials, multidose vials and a single-patient-use KwikPen. Follow the instructions for the exact product.

How many units is 2.5 mg of tirzepatide?

It depends on the vial and the volume. From a 10 mg vial holding 2 mL (5 mg/mL), 2.5 mg is 0.5 mL, or 50 units. From a 30 mg vial holding 3 mL (10 mg/mL), it's 0.25 mL, or 25 units. Enter your own vial above.

How much bac water for a 10 mg tirzepatide vial?

The arithmetic doesn't pick a volume: 1 mL makes 10 mg/mL, 2 mL makes 5 mg/mL and 3 mL makes about 3.33 mg/mL. The volume should come from the vial's instructions or a pharmacist. The bac water calculator finds the volume for a concentration you choose.

My vial is already liquid. Can I use this?

Yes. Enter the milligrams in the vial and its total volume, or divide them yourself to get mg/mL. If the label gives the concentration directly, a 10 mg/mL vial is the same as 10 mg in 1 mL.

Does the calculator include a dose schedule?

No. Doses and when to change them come from your prescriber. This page turns a dose you already have into syringe units and back.