Free tool · Dose → syringe units · Arithmetic only
Semaglutide Dosage Calculator
This tool starts from a dose you already have — a figure in mg someone gave you — and converts it into what it looks like on a U-100 insulin syringe, once you tell it the vial size and water added. It needs the same three numbers as reconstitution; it just skips straight to the draw.
Mixing a vial for the first time? Use the semaglutide reconstitution calculator instead — it solves the water volume from a target strength or unit mark. Both run the same engine, and neither one proposes a dose.
The math, before you use the tool
- Concentration
- mg/mL = vial (mg) ÷ bacteriostatic water (mL)
- Volume to draw
- mL = dose (mg) ÷ concentration (mg/mL)
- Syringe units
- units = volume (mL) × 100 [U-100: 100 marks = 1 mL]
- Draws per vial
- draws = vial (mg) ÷ dose (mg)
One unit mark is 0.01 mL. At 2.5 mg/mL each mark carries 0.025 mg — small in absolute terms, but a real fraction of a sub-milligram dose, which is why the concentration is worth double-checking before trusting the reading.
Read this before you use the calculator
This tool performs unit arithmetic on numbers you enter, and nothing else. It is not medical advice, it does not recommend a dose, and it is not a suggestion that you use any compound. Most of the peptides these calculators get used with are not FDA-approved for the purposes they are marketed for, are sold through a grey market where purity and labelling are not guaranteed, and many are prohibited in tested sport — check yours with the WADA prohibited-status checker. Any decision to use a compound, and any amount, must come from a licensed clinician who knows your history. The FDA-approved semaglutide products are supplied ready to inject in pre-filled pens at a fixed strength and are never reconstituted by the patient — a vial of powder you mix yourself is not one of them, and its contents have not been independently verified.
Enter the vial size, the water you added, and the amount you are working out. Every field starts blank on purpose — this tool converts your numbers, it does not supply them.
This is arithmetic, not advice. Every figure above is derived only from the numbers you typed. Nothing here is a recommended dose, a claim that any compound is approved, safe, or effective, or a suggestion that you should use one. Confirm the vial label, the water volume, and the amount with a licensed clinician before you draw anything.
Worked examples
Real numbers, every step shown, so you can check the tool against a pen and paper. These illustrate the arithmetic — the amounts in them are inputs chosen to make the maths legible, not amounts anyone should use.
A dose of 0.25 mg, at 2.5 mg/mL (a 5 mg vial in 2 mL)
- 1Volume: 0.25 mg ÷ 2.5 mg/mL = 0.1 mL
- 2Units: 0.1 mL × 100 = 10 units
- 3Draws per vial: 5 mg ÷ 0.25 mg = 20
10 units on a U-100 syringe · 20 draws from the vial
The same 0.25 mg dose, at 5 mg/mL (the same vial in 1 mL)
- 1Volume: 0.25 mg ÷ 5 mg/mL = 0.05 mL
- 2Units: 0.05 mL × 100 = 5 units
- 3Draws per vial: unchanged at 20
5 units — half the marks for the same dose, so each mark is worth twice as much
A dose of 1 mg, at 5 mg/mL (a 10 mg vial in 2 mL)
- 1Volume: 1 mg ÷ 5 mg/mL = 0.2 mL
- 2Units: 0.2 mL × 100 = 20 units
- 3Draws per vial: 10 mg ÷ 1 mg = 10
20 units · 10 draws from the vial
Frequently asked questions
- How do I calculate a semaglutide dose in syringe units?
- Divide the vial's mg by the bacteriostatic water in mL for the concentration, divide the dose you were given (in mg) by that concentration for the volume in mL, then multiply by 100 for U-100 syringe units. Example: at 2.5 mg/mL — a 5 mg vial in 2 mL — a 0.25 mg dose is 0.1 mL, which is 10 units.
- What is the standard semaglutide dosage?
- The FDA-approved products (Ozempic, Wegovy) follow a titration schedule printed on their labels, starting low and increasing over weeks under a clinician's supervision — that schedule applies to the approved, pre-filled pen at its labelled strength, not to a compounded vial of unverified potency. This calculator does not reproduce or suggest that schedule; it converts a dose figure you already have into units.
- Do the approved semaglutide products need reconstituting?
- No. Ozempic and Wegovy are supplied as ready-to-inject solution in pre-filled pens at a fixed labelled strength — the patient never mixes powder and water. A lyophilized vial and a bottle of bacteriostatic water is not one of the approved products, and its identity and purity have not been independently verified.
- How many units is 0.25 mg of semaglutide?
- Only the concentration decides. At 2.5 mg/mL it is 10 units. At 5 mg/mL the same 0.25 mg is 5 units. At 1 mg/mL it is 25 units. Because semaglutide amounts are sub-milligram, a single misread unit mark is a much larger relative error here than for a milligram-scale compound — enter your actual concentration rather than reusing a figure from somewhere else.
- Why do sub-milligram semaglutide amounts feel harder to get right?
- Because the absolute size of a reading error stays the same while the dose gets smaller, so the relative error grows. Misreading by one unit mark at 2.5 mg/mL is 0.025 mg — small next to 2.5 mg, but ten percent of a 0.25 mg figure. Choosing a water volume that spreads the amount across more marks (the reconstitution calculator's 'water to add' mode) is the actual fix.
- Does this calculator tell me how much semaglutide to take?
- No. It converts a dose figure you already have into millilitres and syringe units and does nothing else. Every field starts blank, nothing is pre-filled, and the vial-strength chips set a container size, not an amount. It is not medical advice, and any dose decision belongs with a licensed clinician.
The part a calculator cannot answer
A number on a syringe is the easy half. Whether a compound does anything in humans, whether it is legal to buy, and whether it will end a season are the questions worth your time:
- Semaglutide reconstitution calculator — solve the water volume
- How to reconstitute peptides, step by step
- How to inject peptides: subcutaneous vs. intramuscular
- BPC-157 dosage: what the evidence actually says
- TB-500 dosage: what the evidence actually says
- Are GH peptides safe and legal?
- Peptide vendor red flags and scams
- All Peptide Sport tools and calculators
Medical disclaimer: This content is for general educational purposes only and is not medical advice, diagnosis, or treatment. Always consult a licensed healthcare professional before starting, stopping, or changing any treatment.
This calculator converts units. It does not account for your health, the specific product in your hand, its actual purity, injection technique, or whether using it is appropriate at all. Nothing on this page states or implies that any compound is FDA-approved, safe, or effective. Talk to a licensed clinician before acting on any figure here.