Semaglutide 10 mg reconstitution calculator
How much bac water for semaglutide 10 mg?
There’s no single right amount: the water sets the strength, not how much semaglutide is in the vial, so use the volume on your pharmacy’s instructions. For example, 1 mL makes 10 mg/mL and 2 mL makes 5 mg/mL; the table below shows what each volume means on a U-100 syringe.
Your semaglutide vial
Syringe
1 mL · 2-unit marks
Work backwards
Find the water for a given reading in units.
Enter your numbers to see the result.
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This is arithmetic, not medical advice. Confirm with your prescriber or pharmacist.
How our calculator worksAdvanced
Vial capacityOptional
The volume printed on the vial or its box, not the mg. We’ll tell you if the water won’t fit.
What each volume makes
| Water | Strength | Each unit | 1 mg is |
|---|---|---|---|
| 1 mL | 10 mg/mL | 100 mcg | 10 units |
| 2 mL | 5 mg/mL | 50 mcg | 20 units |
| 2.5 mL | 4 mg/mL | 40 mcg | 25 units |
Examples; use the volume on your pharmacy’s instructions. Units are on a U-100 syringe: 100 units = 1 mL.
About the 10 mg vial
More semaglutide than a Wegovy FlexTouch pen
The largest Wegovy pen, FlexTouch, holds 9.6 mg in 3 mL (3.2 mg/mL) and delivers four doses of 2.4 mg; it can only be set to 2.4 mg (Wegovy label). This vial holds 10 mg in less liquid: 4 mg/mL with 2.5 mL of water, 5 mg/mL with 2 mL and 10 mg/mL with 1 mL. That last mix is stronger than any Wegovy injection, including the 7.2 mg/0.75 mL single-dose pen (9.6 mg/mL). Wegovy’s single-dose pens come with the dose already set, so there’s no syringe reading to carry over from them. Work out your units from the mg your prescriber gave you, at the strength on your vial’s label.
Twice the 5 mg vial at the same water
The same water makes this vial twice as strong as the 5 mg vial. With 2 mL it’s 5 mg/mL (0.05 mg per unit) against 2.5 mg/mL (0.025 mg per unit), so the same syringe reading holds twice the semaglutide. Mixing up the two vial sizes doubles or halves what you draw. Equal strengths take twice the water: 10 mg in 2 mL and 5 mg in 1 mL are both 5 mg/mL. The FDA says confusion between mL, mg and units may have contributed to reported dosing errors with compounded semaglutide (FDA), so recalculate whenever your vial size or water changes, and confirm the units with your pharmacist.
Up to 40 draws, but only 28 days
A bigger vial means more draws, not more time. At 0.25 mg, the first step on the Ozempic and Wegovy labels, 10 mg is 40 draws; at 2.4 mg, a Wegovy maintenance dose, it’s 4 with a little left over (Wegovy label, Ozempic label). Both injections are labeled once weekly, and the FDA says to discard a compounded multi-dose vial within 28 days of first use, even if medicine remains and even if the compounder’s instructions allow longer (FDA). At once a week, that’s about four draws. Your prescriber sets your amount; the calculator above shows how many draws the vial holds, so count them against the date before you mix. The FDA also says not to use an injectable GLP-1 that arrives warm, and to use a new sterile needle and syringe for every dose.
Check what else is in the vial
Some compounders add other ingredients to semaglutide, such as vitamin B12 (cyanocobalamin), vitamin B6, L-carnitine or NAD. The FDA notes that the safety and effectiveness of combining semaglutide with other ingredients hasn’t been established (FDA), and compounded drugs aren’t FDA-approved in the first place (FDA). If your label lists more than one ingredient, enter only the semaglutide mg as the vial size: the mg and units on this page then refer to semaglutide alone. If the label gives only a combined total, or you can’t tell how much is semaglutide, ask the pharmacist before you mix.
Sources for these notes
- WEGOVY (semaglutide) injection and tablets, prescribing informationDailyMed, U.S. National Library of Medicine, 2026 (opens in a new tab)
- FDA alerts health care providers, compounders and patients of dosing errors associated with compounded injectable semaglutide productsU.S. Food and Drug Administration, 2024 (opens in a new tab)
- WEGOVY (semaglutide) injection and tablets, prescribing informationDailyMed, U.S. National Library of Medicine, 2026 (opens in a new tab)
- OZEMPIC (semaglutide) injection, prescribing informationDailyMed, U.S. National Library of Medicine, 2026 (opens in a new tab)
- FDA’s Concerns with Unapproved GLP-1 Drugs Used for Weight LossU.S. Food and Drug Administration, 2026 (opens in a new tab)
- FDA alerts health care providers, compounders and patients of dosing errors associated with compounded injectable semaglutide productsU.S. Food and Drug Administration, 2024 (opens in a new tab)
- Compounding and the FDA: Questions and AnswersU.S. Food and Drug Administration, 2025 (opens in a new tab)
About semaglutide
US regulatory status
FDA-approved prescription drug
Novo Nordisk makes every FDA-approved semaglutide product. Ozempic injection is approved for adults with type 2 diabetes to improve blood sugar, to lower the risk of major cardiovascular events in those with established cardiovascular disease, and to lower the risk of kidney function decline, kidney failure and cardiovascular death in those with chronic kidney disease. Rybelsus and Ozempic tablets share one label: once-daily tablets for adults with type 2 diabetes, to improve blood sugar and to lower the risk of major cardiovascular events in those at high risk, and they are not interchangeable mg for mg. Wegovy injection is approved for long-term weight reduction in adults and children 12 and older with obesity, and in adults with overweight and a weight-related condition; to lower the risk of cardiovascular death, heart attack and stroke in adults with cardiovascular disease and obesity or overweight (since March 2024); and, under accelerated approval since August 2025, for noncirrhotic MASH with moderate to advanced liver fibrosis in adults. Its 7.2 mg dose, Wegovy HD, was approved on March 19, 2026, for weight reduction in adults only. Wegovy tablets, approved on December 22, 2025, are for adults, for weight reduction and heart risk reduction, and are not approved for MASH or for children. Compounded semaglutide is not FDA-approved: the FDA declared the shortage resolved on February 21, 2025, its grace periods for compounders ended in 2025, and on April 30, 2026 it proposed excluding semaglutide from the list outsourcing facilities may compound from (no final decision as of this date). Salt forms such as semaglutide sodium and acetate are different active ingredients from the approved drugs, and the FDA has sent warning letters to sellers of semaglutide labeled “for research purposes” or “not for human consumption”.
As of
Sources (13)
- OZEMPIC (semaglutide) injection, prescribing informationDailyMed, U.S. National Library of Medicine, 2026 (opens in a new tab)
- RYBELSUS and OZEMPIC (semaglutide) tablets, prescribing informationDailyMed, U.S. National Library of Medicine, 2026 (opens in a new tab)
- WEGOVY (semaglutide) injection and tablets, prescribing informationDailyMed, U.S. National Library of Medicine, 2026 (opens in a new tab)
- Drugs@FDA: NDA 218316 (WEGOVY tablets), approval historyU.S. Food and Drug Administration, 2026 (opens in a new tab)
- Drugs@FDA: NDA 213051 (RYBELSUS and OZEMPIC tablets), approval historyU.S. Food and Drug Administration, 2026 (opens in a new tab)
- FDA Approves Fourth Product Under National Priority Voucher Program, Higher Dose SemaglutideU.S. Food and Drug Administration, 2026 (opens in a new tab)
- FDA Approves Treatment for Serious Liver Disease Known as ‘MASH’U.S. Food and Drug Administration, 2025 (opens in a new tab)
- FDA Approves First Treatment to Reduce Risk of Serious Heart Problems Specifically in Adults with Obesity or OverweightU.S. Food and Drug Administration, 2024 (opens in a new tab)
- Compounding and the FDA: Questions and AnswersU.S. Food and Drug Administration, 2025 (opens in a new tab)
- FDA clarifies policies for compounders as national GLP-1 supply begins to stabilizeU.S. Food and Drug Administration, 2026 (opens in a new tab)
- FDA Proposes to Exclude Semaglutide, Tirzepatide, and Liraglutide on 503B Bulks ListU.S. Food and Drug Administration, 2026 (opens in a new tab)
- FDA’s Concerns with Unapproved GLP-1 Drugs Used for Weight LossU.S. Food and Drug Administration, 2026 (opens in a new tab)
- Warning letter: TXP Innovations LLC dba Tex Peptides (MARCS-CMS 735067)U.S. Food and Drug Administration, 2026 (opens in a new tab)
How this semaglutide calculator works
This calculator starts from the 10 mg in your vial. Add the water you mix it with and the dose your prescriber gave you; it divides the mg by the mL to get the strength, then turns your dose into mL and units on a 30, 50 or 100-unit syringe.
Peptinote never suggests a dose or a water volume. The example volumes are there to make the math easy to check, not as advice. For the full method, see the peptide calculator.
Questions people ask
How much bacteriostatic water for 10 mg of semaglutide?
There’s no single right amount: use the volume on your pharmacy’s instructions. The water only sets the strength; the vial still holds 10 mg however much you add. With 1 mL it’s 10 mg/mL (100 mcg per unit), with 2 mL 5 mg/mL (50 mcg per unit) and with 2.5 mL 4 mg/mL (40 mcg per unit). Enter your volume and prescribed dose above to get the units.
How do I reconstitute a 10 mg semaglutide vial?
Wipe both stoppers with alcohol and let them dry. Draw the volume of bacteriostatic water your pharmacy specifies into a new syringe, add it slowly down the inside of the vial, then swirl gently until clear; don’t shake. Label it with the strength: 10 mg in 1 mL is 10 mg/mL. Full steps: how to reconstitute peptides.
How do I mix semaglutide powder in a 10 mg vial?
Mixing your semaglutide 10 mg vial takes the bacteriostatic water your pharmacy specifies and a new sterile syringe. Add the water slowly against the glass and swirl, never shake, until the liquid is clear. If it stays cloudy or has particles, don’t use it; call your pharmacy. Then write the strength and date on the vial and store it as the label says (how to store peptides).
Semaglutide 20 units is how many mg?
It depends on the strength of your mixed vial. 20 units is 0.2 mL, and mg = units ÷ 100 × mg/mL. In a 10 mg vial, with 1 mL (10 mg/mL) it holds 2 mg, with 2 mL (5 mg/mL) it holds 1 mg and with 2.5 mL (4 mg/mL) it holds 800 mcg.
Semaglutide 40 units is how many mg?
It depends on the strength of your mixed vial. 40 units is 0.4 mL, and mg = units ÷ 100 × mg/mL. In a 10 mg vial, with 1 mL (10 mg/mL) it holds 4 mg, with 2 mL (5 mg/mL) it holds 2 mg and with 2.5 mL (4 mg/mL) it holds 1.6 mg.
Where are 8 units on a syringe of semaglutide?
8 units is 0.08 mL. On a 30 or 50-unit syringe: the third small line after the 5 line. On a 100-unit syringe: the fourth small line after the start of the scale. What it holds depends on your vial’s strength: at 10 mg/mL it’s 800 mcg. Try it in the syringe reader.
How do semaglutide units convert to mg in a 10 mg vial?
Units measure volume (1 unit = 0.01 mL), so converting them to mg needs the strength: mg = units ÷ 100 × mg/mL. In a 10 mg vial, with 1 mL each unit holds 100 mcg, with 2 mL each unit holds 50 mcg and with 2.5 mL each unit holds 40 mcg. Multiply by the units you draw, or let the calculator above do it, with every step shown.
Is there a peptide calculator for semaglutide?
This page is the semaglutide 10 mg reconstitution calculator. Enter the water you add (or tap an example volume) and your prescribed dose, and it shows the units to draw on a 30, 50 or 100-unit syringe, the strength, and the doses in the vial, with every step of the math. It never suggests a dose.
Can Peptinote tell me how many units to take?
No. Peptinote never suggests a dose. Enter the dose your prescriber gave you, and the calculator shows how to measure it: the units, the mL and where the line sits on your syringe, with every step of the math. If you aren’t sure what your dose is, ask your prescriber or pharmacist before drawing anything. How our calculator works.
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Every result is plain arithmetic from formulas we publish in full and check with automated tests. Peptinote doesn’t suggest doses and never sells or links to sellers of peptides.