Tirzepatide Dosage Chart: Vial Size to Syringe Units

A tirzepatide dosage chart maps a vial's labeled mg amount and the bacteriostatic water added to it into the number that matters at the syringe: units. Tirzepatide ships as lyophilized powder, so the mg on the label is fixed, but concentration is not — it depends entirely on how much water goes into the vial. This chart works through that math for the vial sizes tirzepatide research vials are commonly supplied in. It is a reference for research and educational purposes only and is not medical advice.

The reference concentration

There is no single required water volume for tirzepatide. A reference point commonly cited across tirzepatide research materials scales the water to the vial size at 1 mL per 10 mg, which holds the concentration at a constant 10 mg/mL no matter which vial size is on hand:

Vial size	Water added	Concentration
5 mg	0.5 mL	10 mg/mL
10 mg	1 mL	10 mg/mL
15 mg	1.5 mL	10 mg/mL
30 mg	3 mL	10 mg/mL
60 mg	6 mL	10 mg/mL

Because the ratio scales with vial size, the units for a given dose stay identical across all five rows — only the total number of doses each vial holds changes. For the full mixing procedure behind these numbers, see the tirzepatide reconstitution calculator guide.

Tirzepatide dosage chart by target dose

Each row below assumes the 10 mg/mL reference concentration and shows the resulting draw on a U-100 insulin syringe (100 units per mL):

Target dose	Volume	Units
2.5 mg	0.25 mL	25 units
5 mg	0.5 mL	50 units
7.5 mg	0.75 mL	75 units
10 mg	1 mL	100 units

A 5 mg dose landing on an exact 50-unit mark is a large part of why 10 mg/mL is the reference concentration most tirzepatide charts default to — every dose in the table above reads cleanly on a standard U-100 barrel, right up to a full 1 mL syringe at the 10 mg step.

Reading the chart against a specific vial

Worked example. A 30 mg vial mixed with 3 mL of bacteriostatic water sits at 30 ÷ 3 = 10 mg/mL. For a 5 mg target dose: 5 ÷ 10 = 0.5 mL, and 0.5 mL × 100 = 50 units on a U-100 syringe.

Compare that to the same 5 mg dose drawn from a 10 mg vial mixed with 1 mL of water — also 10 mg/mL: 5 ÷ 10 = 0.5 mL, or 50 units again. The dose in mg is identical, and so is the unit reading, because both vials were reconstituted to the same concentration. What differs is supply: the 10 mg vial holds 10 ÷ 5 = 2 doses at 5 mg each, while the 30 mg vial holds 30 ÷ 5 = 6 doses.

Vial size sets dose count, water volume sets draw size

Vial size and water volume do different jobs, and conflating them is the most common misread of a chart like this one. Vial size sets the total mg of tirzepatide available across the whole vial. Water volume sets concentration, which is what determines the units for any single draw.

At a 2.5 mg dose, a 5 mg vial provides 5 ÷ 2.5 = 2 doses. A 60 mg vial at that same 2.5 mg dose provides 60 ÷ 2.5 = 24 doses — 12 times the doses, because it holds 12 times the tirzepatide (60 ÷ 5), not because it was mixed differently. Water volume, by contrast, changes only the draw size per dose, not how many doses the vial holds in total.

When your vial doesn't match the reference ratio

A vial mixed with a different water volume still follows the same formula — it just won't land on the chart above. Take a 15 mg vial mixed with 1 mL of water instead of the reference 1.5 mL: concentration is 15 ÷ 1 = 15 mg/mL. A 5 mg target dose at that concentration is 5 ÷ 15 = 0.3333 mL, or roughly 33.3 units — a fractional reading that doesn't sit cleanly on a syringe marked in whole units.

That's a signal to change the water volume rather than round the draw up or down. This is the case the peptide calculator is built for: enter the vial size and water volume you actually used, and it runs the same concentration-to-units math for any combination, not just the round numbers in a reference chart. Its reverse mode also works the other direction — enter a target dose and a desired unit reading, and it returns the water volume that produces it.

Vial size and protocol length

Vial size questions come up most often when planning how many vials a protocol needs, not just how a single draw reads. A 60 mg vial at a 5 mg dose supplies 60 ÷ 5 = 12 doses; a 15 mg vial at that same dose supplies only 15 ÷ 5 = 3 doses. None of that changes the units on the syringe for any single draw — it only changes how many times the vial can be drawn from before it's empty. For that side of the math, see the tirzepatide vial size guide.

Common mistakes

• Reading a unit count from this tirzepatide dosage chart against the wrong vial. A number in the table only applies if the vial was actually mixed to the 10 mg/mL reference concentration. Confirm the water volume used before drawing.
• Assuming vial size sets the dose. It sets the total mg available across the vial. Concentration — set by water volume — is what determines units per dose.
• Mixing up mg and mcg. Tirzepatide vials and doses are generally labeled in milligrams, not micrograms (1 mg = 1,000 mcg). A missed decimal here is a thousand-fold error.
• Rounding mid-calculation. Carry the full decimal through the mL step and only round the final unit reading, and only if the syringe requires it.

Use the calculator

This tirzepatide dosage chart covers the common 10 mg/mL reference concentration, but your vial and target dose may not match it exactly. Enter your vial size, water volume, and target dose into the free peptide calculator for an exact unit count, or run its reverse mode to find the water volume that lands a given dose on a whole unit mark. For the step-by-step mixing process, see how to reconstitute peptides, and for how vial size translates into total doses per vial, see the tirzepatide vial size guide.