Tirzepatide dosage calculator

Tirzepatide dosage calculator: mg to units

Tirzepatide is prescribed in mg, but an insulin syringe is marked in units. Enter the strength printed on your vial (mg/mL) and your dose to get the line to draw to. The chart covers every label dose step at common strengths.

Any mg/mL strength
Units chart 2.5–15 mg
Label schedule, sourced
Units → mg lookup

Start calculating See the chart

Tirzepatide units calculator

Draw to

—

units
on U-100

Enter the vial, the mix and the dose to see where to draw.

—mg/mL

Concentration

—mL

Volume to draw

—doses

Doses per vial

—days

Vial lasts (set frequency)

U-100 · 1 mL (100 units)

Drawn to scale

Worked example

25 units, step by step

The example numbers show how the math works. They are not a dose recommendation.

1The vial label says 10 mg/mL.
2A 2.5 mg dose: 2.5 ÷ 10 = 0.25 mL.
30.25 mL × 100 = 25 units on a U-100 syringe.

Tirzepatide dosage chart in units

Units on a U-100 syringe for each label dose step, by vial strength. The strengths are those of the labelled single-dose vials (2.5 to 15 mg in 0.5 mL); read the strength on your own vial.

Tirzepatide: units for each dose step

Dose / Concentration	5 mg/mL	10 mg/mL	15 mg/mL	20 mg/mL	25 mg/mL	30 mg/mL
2.5 mg	50 u	25 u	16.7 u	12.5 u	10 u	8.3 u
5 mg	100 u	50 u	33.3 u	25 u	20 u	16.7 u
7.5 mg	> 1 mL	75 u	50 u	37.5 u	30 u	25 u
10 mg	> 1 mL	100 u	66.7 u	50 u	40 u	33.3 u
12.5 mg	> 1 mL	> 1 mL	83.3 u	62.5 u	50 u	41.7 u
15 mg	> 1 mL	> 1 mL	100 u	75 u	60 u	50 u

Units on a U-100 insulin syringe (100 units = 1 mL). “> 1 mL” means the dose does not fit a 1 mL syringe at that strength. Computed by the same formula as the calculator.

Zepbound

Label schedule

Weeks 1–42.5 mg once weeklyStarting dose only; not a maintenance dose.
Week 5 on5 mg once weekly
Further steps+2.5 mgAfter at least 4 weeks on the current dose.
Maintenance5, 10 or 15 mg once weeklyWeight reduction. For sleep apnea: 10 or 15 mg.
Maximum15 mg once weekly

Single-dose pen or vial: 2.5, 5, 7.5, 10, 12.5 or 15 mg in 0.5 mL.
Multi-dose vial and KwikPen: 4 doses of 0.6 mL (10–60 mg in 2.4 mL).

Source: Zepbound US Prescribing Information, sections 2 and 3 (Eli Lilly; Revised 08/2026; DailyMed, checked 2026-09-30). Label schedule only: follow your prescriber.

Mounjaro

Label schedule

Start2.5 mg once weekly
Increase+2.5 mgIf more glucose control is needed, after at least 4 weeks on the current dose.
Maximum15 mg once weekly (adults)

Single-dose pen or vial: 2.5–15 mg in 0.5 mL.
Multi-dose vial and KwikPen: 4 doses of 0.6 mL.

Source: Mounjaro US Prescribing Information, section 2 (Eli Lilly; DailyMed SPL effective 2026-08-27; DailyMed, checked 2026-09-30). Label schedule only: follow your prescriber.

Units → mg

Already know the units? Enter them with your vial strength to see the dose in mg (U-100 syringe).

Units on the syringe

units

Vial concentration

mg/mL

—

Why the units depend on your vial

The same mg dose takes a different number of units in every vial strength. Always start from the concentration on your vial label. If a label lists a total amount and a total volume instead (for example mg per 2 mL), divide the two to get mg/mL, or switch the calculator to Powder vial and enter both.

Labelled vials use fixed volumes

In the US prescribing information, each single-dose vial holds one dose in 0.5 mL, and each multi-dose vial gives 4 doses of 0.6 mL. The label describes these in mL, not units, and asks for a syringe that can measure the dose, such as a 1 mL syringe. On a U-100 syringe 0.5 mL is the 50-unit line and 0.6 mL the 60-unit line, which is what the calculator shows when you enter the matching strength.

Vials made up by a pharmacy can come in other strengths. The calculator works for any strength; the chart above only lists the labelled ones.

Sources (checked 30 September 2026)

Reading the schedule

The label schedule starts at 2.5 mg once weekly, a starting dose only, and moves up in 2.5 mg steps, each after at least 4 weeks on the current dose, to a maximum of 15 mg once weekly. It is shown here so you can check the number you were given. Your prescriber sets your own dose and timing.

About this page

Who made it, and how

Made by FangFang, an independent app studio run by Fang Fang in Auckland, New Zealand.

We draft with AI assistance. Facts are checked against the primary sources linked on the page (US prescribing information and product labels on DailyMed, CDC and NLM pages), each with the date it was checked. Every number comes from the calculator’s own formula, which is covered by automated tests, including the worked example above. A person reviews the page before it is published. No doctor or pharmacist has reviewed it, which is why it sticks to arithmetic and quoted labels.

Last reviewed 30 September 2026

FAQ

Questions

How many units is 2.5 mg of tirzepatide?

It depends on the vial strength. At 5 mg/mL, 2.5 mg is 50 units on a U-100 syringe; at 10 mg/mL it is 25 units; at 20 mg/mL it is 12.5 units. Enter the strength on your vial to get yours.

How many units is 5 mg of tirzepatide?

At 10 mg/mL, 5 mg is 50 units; at 20 mg/mL it is 25 units. At 5 mg/mL it takes 100 units, a full 1 mL syringe. The chart shows every label dose step.

What is the tirzepatide dosing schedule on the label?

The US label starts at 2.5 mg once weekly for 4 weeks, then 5 mg. Increases are 2.5 mg at a time, after at least 4 weeks on the current dose, up to 15 mg once weekly. Follow the schedule your prescriber gives you.

Which syringe should I use for tirzepatide?

Use the syringe your pharmacist supplies. The calculator tells you if a dose will not fit: a 0.5 mL syringe holds up to 50 units, a 1 mL syringe up to 100. The label itself mentions a 1 mL syringe able to measure 0.5 or 0.6 mL.

Does the calculator tell me what dose to take?

No. It only converts the dose you already have into mL and syringe units. It has no default doses and does not check whether a dose is right for you. Your prescriber or pharmacist decides the dose and how to prepare it.

Is anything I type sent or stored?

The math runs in your browser and nothing you type is sent to us. To save retyping, your last inputs are kept in this browser’s local storage; the Reset button clears them.