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Your dose, in units.
Tirzepatide and semaglutide dosage calculator: mg to units
By the NexLife Medical Team · Medically reviewed by Adam Kennah, MD · Updated
Units = dose in mg ÷ vial strength in mg/mL × 100 on a U-100 syringe. At an example 25 mg/mL, 2.5 mg of tirzepatide is 0.1 mL, or 10 units.
- A calculator for your dose and your vial’s strength
- Two worked examples for each medicine, and a units chart
- One number to call: (949) 818-8000, 24/7
The math, at a glance
- The formula
- mL = mg ÷ mg/mL; units = mL × 100
- Tirzepatide example
- 2.5 mg = 10 units at an example 25 mg/mL
- Semaglutide example
- 0.25 mg = 10 units at 2.5 mg/mL, or 5 units at 5 mg/mL
- Your strength
- On your vial’s label; recheck it on every new vial
Units don’t match your instructions? NexLife patients, call or text (949) 818-8000, 24/7, before you draw.
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Key takeaways
- The formula: units on a U-100 syringe = your dose in mg ÷ your vial’s strength in mg/mL × 100.
- Strength changes the units. 0.25 mg of semaglutide is 10 units at 2.5 mg/mL, but 5 units at 5 mg/mL.
- Read your own label. Strengths of compounded medicines vary, so use the mg per mL printed on your vial, never a chart’s example.
- 100 units is 1 mL. The FDA has had reports of people injecting five to 20 times their intended dose of compounded semaglutide.
- It checks math, not doses. Your provider sets your dose. If the units don’t match your instructions, ask before you draw.
- At NexLife, compounded tirzepatide is $139 a month on the 12-month plan, the same at every dose, and you can ask dosing questions 24/7.
Free calculator
How many units is your dose?
Pick your medicine, then enter the strength printed on your vial’s label and the dose your provider prescribed: it shows the mL and the units on a U-100 insulin syringe.
It only does the math, for U-100 insulin syringes, with units rounded to one decimal place. It can’t read your label or tell you whether a dose is right for you. The dose buttons are the Zepbound and Wegovy label steps; your prescription comes first.
The formula
How do you convert mg to units?
Divide your dose in mg by your vial’s strength in mg per mL to get mL, then multiply by 100 to get units on a U-100 insulin syringe.
mL = dose in mg ÷ strength in mg/mL, and units = mL × 100, because a U-100 syringe holds 100 units in 1 mL. Here are two worked examples for each medicine, at example strengths only.
Tirzepatide 2.5 mg at 25 mg/mL
2.5 ÷ 25 = 0.1 mL. 0.1 × 100 = 10 units. It’s the starting dose on Zepbound’s label.
Tirzepatide 7.5 mg at 25 mg/mL
7.5 ÷ 25 = 0.3 mL. 0.3 × 100 = 30 units. Three times the dose is three times the units.
Semaglutide 0.25 mg at 2.5 mg/mL
0.25 ÷ 2.5 = 0.1 mL. 0.1 × 100 = 10 units. It’s the starting dose on Wegovy’s label.
Semaglutide 1.7 mg at 5 mg/mL
1.7 ÷ 5 = 0.34 mL. 0.34 × 100 = 34 units. At 2.5 mg/mL, the same dose would be 68 units.
Going the other way? mg = units × strength in mg/mL ÷ 100. At 25 mg/mL, 20 units is 20 × 25 ÷ 100 = 5 mg.
These strengths are examples only. 25 mg/mL is the strength of the 15 mg multi-dose vial on Zepbound’s label (15 mg in 0.6 mL), and 2.5 and 5 mg/mL are example strengths for semaglutide. Read the strength on your own vial’s label.
Step by step
How do you work out your dose in units, step by step?
Five steps, shown with one example: 2.5 mg of tirzepatide from a vial at an example 25 mg/mL. Your label sets the strength; your prescription sets the dose.
- Find your dose in mg. It’s on your prescription, and your provider sets it. In the example, 2.5 mg.
- Find your vial’s strength. It’s on the label, in mg per mL. If the label shows a total over a volume, divide: 15 mg in 0.6 mL is 25 mg/mL.
- Divide the dose by the strength. That’s your dose in mL: 2.5 mg ÷ 25 mg/mL = 0.1 mL.
- Multiply by 100. That’s the units on a U-100 insulin syringe: 0.1 mL × 100 = 10 units. The calculator above does steps 3 and 4 for you.
- Check before you draw. If the units don’t match your instructions, the strength changed or the answer is over 100 units, don’t inject: ask first. NexLife patients, call or text (949) 818-8000, 24/7.
Units chart
How many units is each tirzepatide and semaglutide dose?
It depends on your vial’s strength: at these example strengths, the starting dose is 10 units of tirzepatide at 25 mg/mL, and 10 or 5 units of semaglutide at 2.5 or 5 mg/mL.
Tirzepatide, at an example 25 mg/mL
| Weekly dose | mL at 25 mg/mL | Units (U-100) | On Zepbound’s label |
|---|---|---|---|
| 2.5 mg | 0.1 mL | 10 units | Starting dose, for 4 weeks |
| 5 mg | 0.2 mL | 20 units | A maintenance dose |
| 7.5 mg | 0.3 mL | 30 units | A step up |
| 10 mg | 0.4 mL | 40 units | A maintenance dose |
| 12.5 mg | 0.5 mL | 50 units | A step up |
| 15 mg | 0.6 mL | 60 units | The maximum, and a maintenance dose |
Semaglutide, at example 2.5 and 5 mg/mL
| Weekly dose | Weeks on Wegovy’s label | At 2.5 mg/mL | At 5 mg/mL |
|---|---|---|---|
| 0.25 mg | 1 to 4 | 0.1 mL (10 units) | 0.05 mL (5 units) |
| 0.5 mg | 5 to 8 | 0.2 mL (20 units) | 0.1 mL (10 units) |
| 1 mg | 9 to 12 | 0.4 mL (40 units) | 0.2 mL (20 units) |
| 1.7 mg | 13 to 16 | 0.68 mL (68 units) | 0.34 mL (34 units) |
| 2.4 mg | 17 onward | 0.96 mL (96 units) | 0.48 mL (48 units) |
On Zepbound’s label, the dose goes up by 2.5 mg after at least 4 weeks on a dose, to a 15 mg maximum. On Wegovy’s, it goes up every 4 weeks to the usual 2.4 mg maintenance dose. Your provider may keep you on a dose longer, or not go higher at all.
Need another strength? The tirzepatide dosage chart and the semaglutide dosage chart show every label dose at more example strengths.
Both tables use example strengths only. The same dose is a different number of units at a different strength, so read the strength on your own vial’s label. Your prescription sets your dose and schedule, which may differ from these label steps.
Avoid these
Which GLP-1 dosing mistakes should you avoid?
Measuring the wrong dose with a syringe: in reports to the FDA, people injected five to 20 times the intended dose of compounded semaglutide.
- Mixing up mL and units. On a U-100 syringe, 0.1 mL is 10 units, not 1 unit. Drawing to 1 mL when your dose is 0.1 mL would be 10 times the dose.
- Using an old vial’s units. A new vial can have a new strength. At 2.5 mg/mL, 10 units is 0.25 mg; at 5 mg/mL, the same 10 units is 0.5 mg, twice as much.
- Reading the wrong lines. On many 1 mL syringes, each line is 2 units, not 1. Check what each line stands for before you draw.
- Rounding on your own. A fraction of a unit is hard to measure on a syringe marked in whole units. Ask exactly what to draw.
- Changing your dose yourself. Only your provider changes your dose. Don’t change, skip or space out a dose on your own.
Think you injected too much? Call your provider or Poison Help at 1-800-222-1222, or go to the nearest emergency room right away, as the Zepbound Medication Guide says.
Not sure about a number? Ask before you inject. NexLife patients: call or text (949) 818-8000, 24/7.
In their words
What does the FDA say about dosing errors with compounded GLP-1s?
Its 2024 alert on compounded semaglutide and its page on unapproved GLP-1 drugs, in its own words.
How far off a dose went, in the reports the FDA described:
“In these instances, patients administered five to 20 times more than the intended dose of semaglutide.”
U.S. Food and Drug Administration, FDA alerts health care providers, compounders and patients of dosing errors associated with compounded injectable semaglutide products, July 26, 2024
What most of the FDA’s reports had in common:
“Most of the reports indicated that patients were unfamiliar with how to measure the intended dose using a syringe.”
U.S. Food and Drug Administration, FDA alerts health care providers, compounders and patients of dosing errors associated with compounded injectable semaglutide products, July 26, 2024
Why no chart, including ours, can stand in for the strength on your own label:
“Product concentrations also may vary depending on the compounder, and a single compounder may offer multiple concentrations of compounded semaglutide products.”
U.S. Food and Drug Administration, FDA alerts health care providers, compounders and patients of dosing errors associated with compounded injectable semaglutide products, July 26, 2024
Measuring isn’t the only risk the FDA has named, and this one covers both medicines:
“Additionally, the agency has received adverse event reports that may be related to patients prescribed compounded semaglutide or tirzepatide products in doses beyond what is in the FDA-approved drug label.”
U.S. Food and Drug Administration, FDA’s Concerns with Unapproved GLP-1 Drugs Used for Weight Loss
U-100 syringes
How do you read units on a U-100 syringe?
Each unit is 0.01 mL, because a U-100 insulin syringe holds 100 units in 1 mL; how much medicine a unit holds depends on your vial’s strength.
10 units of tirzepatide
0.1 mL. At 25 mg/mL, that’s 2.5 mg.
10 units of semaglutide
0.1 mL. At 2.5 mg/mL, that’s 0.25 mg.
The same 10 units
0.1 mL. At 5 mg/mL, that’s 0.5 mg of semaglutide.
Syringe sizes. A 0.3 mL U-100 syringe holds 30 units, a 0.5 mL syringe holds 50 and a 1 mL syringe holds 100. On many 1 mL syringes, each line is 2 units. Use the syringe your pharmacy or provider recommends, big enough to hold your whole dose in one draw.
A new one every time. The FDA and the CDC both say to use a new needle and syringe for every dose, and MedlinePlus notes that needles for under-the-skin shots are very short and thin. Put each used one straight into a sharps container. Step by step: how to inject tirzepatide and how to inject semaglutide.
Before you rely on it
What can’t a GLP-1 dosage calculator tell you?
Whether a dose is right for you: it only turns the dose and strength you type into mL and units.
- Your dose. Your provider sets it, and any change to it.
- Your strength. Only your vial’s label has it. A new vial, or a different pharmacy, can mean a new strength, so recheck the units each time.
- Your syringe. The math works only for U-100 insulin syringes.
- Pens and single-dose vials. Wegovy’s pens and prefilled syringes hold a measured dose, and Lilly’s KwikPen has its own instructions. A Zepbound single-dose vial holds one 0.5 mL dose (50 units on a U-100 syringe). This math is for multi-dose vials, where your units depend on the strength.
- Doses over 100 units. They won’t fit in a 1 mL syringe. The calculator shows a warning: don’t inject, and ask your prescriber.
Moving from a pen to a compounded vial? Your units start from your new label: see Zepbound to compounded tirzepatide or Wegovy to compounded semaglutide.
When to ask first: the units don’t match your instructions, a new vial’s strength is different, or the answer has a fraction you can’t measure. NexLife patients: call or text (949) 818-8000, 24/7.
What would you pay with NexLife?
Tap where you are now. We’ll show your NexLife price next to it, or tell you we’ll match it.
Pick one above to see your price.
Prices from each provider’s own site, checked November 1, 2026. Brand-name and compounded medications are different products: compounded medications aren’t FDA-approved, and a provider prescribes one only when it offers a significant difference for you. Price Match Guarantee† terms apply.
Two medications.
One flat price at every dose.
No membership fee. Provider care, a nutrition plan, coaching and shipping are included. Paying less with another licensed provider? We match your regular monthly price.†
GIP + 12-month plan $139/mo
Tirzepatide
Weekly and dual-action. Care, coaching and shipping included. On a 12-month plan; $169/mo month to month.
Check my eligibilityCompounded, not FDA-approved · Not prescribed? No charge for medication
12-month plan $119/mo
Semaglutide
Weekly
Compounded, not FDA-approved · Not prescribed? No charge for medication
Compounded, not FDA-approved. A licensed provider prescribes it only when it offers a significant difference for you. Vials shown are illustrations. Always use the strength on your pharmacy’s label. Every plan and price · Price Match Guarantee† terms
The NexLife Price Match Guarantee†
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†Terms: see the Price Match Guarantee† details below. Compounded medications aren’t FDA-approved; a provider prescribes one only when it offers a significant difference for you.
Dosage calculator questions
Fair questions about NexLife
- Will my price go up with my dose?
- No. You pay the same at every dose.
- What if I’m not prescribed?
- You aren’t charged for medication.
- Can I cancel?
- Yes, by email. It takes effect 30 days after we receive it. Plans renew until you cancel; our cancellation policy has the details.
- Do I need insurance?
- No. Pay with an HSA or FSA card, or with Affirm, Klarna or Afterpay at checkout.
How do you convert mg to units for tirzepatide or semaglutide?
Divide your dose in mg by your vial’s strength in mg per mL, then multiply by 100. That gives the units on a U-100 insulin syringe. At an example 25 mg/mL, 5 mg of tirzepatide is 5 ÷ 25 = 0.2 mL, or 20 units. Use the strength on your own label, and follow your prescription.
What is a U-100 insulin syringe?
It’s a syringe marked in units, where 100 units equal 1 mL, so each unit is 0.01 mL. A 0.3 mL syringe holds 30 units, a 0.5 mL syringe holds 50 and a 1 mL syringe holds 100. On many 1 mL syringes, each line is 2 units. Use the one your pharmacy or provider recommends.
Is 10 units the same as 0.1 mL?
Yes. On a U-100 syringe, 10 units is 0.1 mL. How much medicine that holds depends on the strength: 2.5 mg of tirzepatide at 25 mg/mL, or 0.25 mg of semaglutide at 2.5 mg/mL and 0.5 mg at 5 mg/mL. That’s why you recheck your units whenever your vial’s strength changes.
How many mg is 20 units of tirzepatide or semaglutide?
It depends on your vial’s strength: mg = units × strength in mg/mL ÷ 100. At an example 25 mg/mL, 20 units of tirzepatide is 5 mg. At 2.5 mg/mL, 20 units of semaglutide is 0.5 mg; at 5 mg/mL, it’s 1 mg. Your prescription sets your dose, so ask if 20 units doesn’t match it.
Why are my units different from someone else’s?
Because your vials may have different strengths. The FDA says concentrations of compounded semaglutide may vary by compounder, and one compounder may offer several. The same 0.25 mg is 10 units at 2.5 mg/mL but 5 units at 5 mg/mL. Don’t copy units from another person, and recheck yours whenever your vial changes.
Can I use a dosage calculator to change my dose?
No. It turns the dose your provider prescribed into mL and units; it doesn’t decide what dose is right for you. Don’t change, skip or space out a dose on your own: your provider decides. If the calculator’s answer doesn’t match your instructions, ask before you draw anything.
What if my dose comes to more than 100 units?
Don’t inject it. More than 100 units is more than 1 mL, which won’t fit in a 1 mL U-100 syringe, and the calculator warns you. Check the strength and the dose you entered, then ask your prescriber. NexLife patients: call or text (949) 818-8000, 24/7.
Do I need to count units with a Wegovy or Zepbound pen?
No. Units are for drawing a dose from a vial with a U-100 syringe. Wegovy’s pens and prefilled syringes hold a measured dose, and Lilly’s KwikPen has its own instructions. Moving from a pen to a compounded vial? Your units depend on the new vial’s strength, so work them out from its label.
How do you read the strength on a vial label?
Look for mg per mL, such as 2.5 mg/mL. Some labels show a total over a volume instead, like 5 mg/2 mL: divide the total by the volume, here 5 ÷ 2 = 2.5 mg/mL. The total in the vial isn’t your dose. If anything doesn’t match your prescription, ask before you inject.
Important safety information
Compounded tirzepatide and semaglutide are not FDA-approved, and the FDA hasn’t reviewed them for safety, effectiveness or quality. A provider prescribes them only when they offer a significant difference for you compared with an FDA-approved product. Both medicines may cause thyroid tumors, including cancer: don’t use either if you or a family member has had medullary thyroid carcinoma (MTC) or multiple endocrine neoplasia syndrome type 2 (MEN 2).
Read the full safety information
In studies with rodents, both medicines caused thyroid tumors; it isn’t known whether they cause them in people. Tell your provider if you notice a lump or swelling in your neck, hoarseness, trouble swallowing or shortness of breath. Serious side effects can include inflammation of the pancreas (pancreatitis), gallbladder problems, low blood sugar (especially with insulin or sulfonylureas), kidney problems from dehydration, severe stomach problems, serious allergic reactions, vision changes in people with type 2 diabetes, and a faster heart rate. Tell your care team before any surgery or procedure that uses anesthesia or deep sedation. Don’t combine either medicine with other
Tirzepatide can make birth control pills less effective: switch to a non-oral method, or add a barrier method such as condoms, for 4 weeks after you start and for 4 weeks after each dose increase. Both medicines may harm an unborn baby. Semaglutide should be stopped at least 2 months before a planned pregnancy. Tell your provider right away if you’re pregnant, planning to be, or breastfeeding.
This is a summary, not the complete safety information. Read the full Prescribing Information for FDA-approved tirzepatide (Zepbound) and semaglutide (Wegovy), and talk with your provider. You can report side effects to the FDA at
† NexLife Price Match Guarantee: for new NexLife members switching from a licensed U.S. telehealth provider or clinic with an active prescription for compounded tirzepatide or semaglutide. We match your regular all-in monthly price there (medication plus any required membership, program or visit fee, on a month-to-month plan); first-month offers, coupons, referral credits and prepaid multi-month rates aren’t matched. Proof from the last 60 days required. A licensed provider must determine that treatment is right for you. Not open to people with Medicare, Medicaid or TRICARE coverage. Full terms.
About NexLife. NexLife is a telehealth and care-coordination platform. Care is delivered through affiliated, physician-owned medical groups, and licensed providers decide whether treatment is right for you. NexLife doesn’t make or compound medication: state-licensed partner pharmacies fill each prescription, and we coordinate the rest. Available only in states where our affiliated providers are licensed.
“Compounded drugs are not FDA-approved. This means that FDA does not verify the safety, effectiveness or quality of compounded drugs before they are marketed.”
Who wrote and checked this page
Leads the NexLife Medical Team, which writes and medically reviews NexLife’s guides, including this one.
Checked the calculator’s math (mL = dose ÷ strength; units = mL × 100) and every worked example against the dose steps on the Zepbound and Wegovy labels, and the dosing-error facts against the FDA’s alert of July 26, 2024.
- Every fact, sourced. Each price and rule links to the page it comes from.
- How we make money. NexLife is a telehealth and care-coordination platform. We earn revenue when people join NexLife.
- Corrections, fast. See something wrong or out of date? Email care@nexlife.us and we’ll fix it.
Paying less elsewhere? We match it.†
Questions about your units? Ask us, 24/7.
Tirzepatide is $139 or semaglutide $119 a month on 12-month plans ($169 and $139 month to month), the same at every dose, and dosing questions come to us 24/7.
4.8 out of 5 on Trustpilot · Medical director Adam Kennah, MD (NPI 1144260043) · LegitScript-certified
Compounded medications aren’t FDA-approved. A provider prescribes one only when it offers a significant difference for you.
- 1Tell us about you
Start online with your health history.
- 2A licensed provider decides
Online, or by secure video where your state requires a live visit. You’re prescribed only if treatment is right for you.
- 3We ship it, then stay with you
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Sources
- U.S. Food and Drug Administration. FDA alerts health care providers, compounders and patients of dosing errors associated with compounded injectable semaglutide products. July 26, 2024.
- U.S. Food and Drug Administration. FDA’s concerns with unapproved GLP-1 drugs used for weight loss.
- Eli Lilly and Company. Zepbound (tirzepatide) prescribing information. Dose steps and the 15 mg multi-dose vial.
- Eli Lilly and Company. Zepbound Medication Guide. What to do if you take too much.
- Eli Lilly and Company. Zepbound single-dose vial: Instructions for Use.
- Eli Lilly and Company. Zepbound KwikPen: Instructions for Use.
- Novo Nordisk. Wegovy (semaglutide) prescribing information, Medication Guide and Instructions for Use. Dose steps and pens.
- Novo Nordisk. Wegovy dosing schedule.
- Centers for Disease Control and Prevention. Preventing unsafe injection practices (multi-dose vials).
- MedlinePlus (National Library of Medicine, NIH). Subcutaneous (SQ) injections.
- U.S. Food and Drug Administration. Sharps disposal containers.
- U.S. Food and Drug Administration. Compounding and the FDA: Questions and Answers.
- U.S. Food and Drug Administration. MedWatch: The FDA Safety Information and Adverse Event Reporting Program.
- NexLife. Compounded tirzepatide plans.
- NexLife. Compounded semaglutide plans.
- LegitScript. LegitScript certification record for NexLife.us.
- Ro: weight loss program pricing. Checked November 1, 2026.
- Hims: Zepbound KwikPen. Checked November 1, 2026.
- Hims: Wegovy pill and pen, with membership. Checked November 1, 2026.
- Mochi Health: FAQs (membership and medication prices). Checked November 1, 2026.
- Embody: compounded tirzepatide, one-month supply. Checked November 1, 2026.
- Embody: compounded semaglutide, one-month supply. Checked November 1, 2026.