How many units is 0.25 mg of semaglutide?

In a 5 mg vial with 2 mL of water the concentration is 2.5 mg/mL, so 0.25 mg is 0.1 mL, which is 10 units on a U-100 syringe.

How much bacteriostatic water for a 5 mg semaglutide vial?

2 mL is the common choice and gives 2.5 mg/mL. That places the 0.25 to 2.4 mg ladder between 10 and 96 units, which fits a 1 mL syringe across the whole range.

Why are my units different from someone else's?

Because they used a different amount of water. Units are only meaningful alongside the vial strength and the water volume. Always state all three.

How many doses in a 10 mg vial?

Divide 10 by your weekly dose. At 0.5 mg that is 20 doses, or 140 days.

Semaglutide dosage calculator

Semaglutide doses are small, so the draw is small and the water volume matters more than with any other compound here. Put in your numbers and see where it lands.

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ReviewedDose ranges and half-life figures last checked 29 August 2026.

Dose to units, at the standard setup

Dose	Draw	U-100 units	Doses per vial	Vial lasts
0.25 mg	0.1 mL	10 units	20	140 days
0.5 mg	0.2 mL	20 units	10	70 days
1 mg	0.4 mL	40 units	5	35 days
1.7 mg	0.68 mL	68 units	2	14 days
2.4 mg	0.96 mL	96 units	2	14 days

Based on a 5 mg vial reconstituted with 2 mL of bacteriostatic water, which is 2.5 mg/mL, drawn on a standard U-100 insulin syringe.

About the numbers above

Semaglutide is a GLP-1 receptor agonist. The licensed ladder is 0.25, 0.5, 1.0, 1.7 and 2.4 mg once weekly, stepping every four weeks, with 0.25 mg as a starting dose rather than a maintenance one.

Because 0.25 mg is a very small quantity, a 5 mg vial reconstituted with 2 mL puts that dose at 10 units. Reconstituting the same vial with only 1 mL halves it to 5 units, where a small misread is a large proportional error. This is the one compound where erring towards more water is usually the easier choice.

Common vial and water combinations


Vial	BAC water	Concentration	Draw	U-100 units	Doses/vial
2 mg	1 mL	2 mg/mL	0.25 mL	25 units	4
2 mg	2 mL	1 mg/mL	0.5 mL	50 units	4
2 mg	3 mL	0.67 mg/mL	0.75 mL	75 units	4
5 mg	1 mL	5 mg/mL	0.1 mL	10 units	10
5 mg	2 mL	2.5 mg/mL	0.2 mL	20 units	10
5 mg	3 mL	1.67 mg/mL	0.3 mL	30 units	10
10 mg	1 mL	10 mg/mL	0.05 mL	5 units	20
10 mg	2 mL	5 mg/mL	0.1 mL	10 units	20
10 mg	3 mL	3.33 mg/mL	0.15 mL	15 units	20

All rows above assume a 0.5 mg dose and a standard U-100 insulin syringe, where 100 units = 1 mL.

How long it stays in you

The half-life of Semaglutide is about 7 days. That is the time for the amount in your blood to halve, so after one half-life you are at 50 percent of the peak, after two you are at 25 percent, and after four you are at roughly 6 percent. This is why a weekly compound still has meaningful levels present when the next dose lands, and why levels build over the first several weeks before they settle.

Free: The Protocol Pack, 25 printable pages. Including the part no other site writes down: what to do when you have already got it wrong. Wrong water volume, shook the vial, left it out overnight, drew the wrong units. Plus dosing cards for twelve compounds, titration planners and a vial log. Get it free.

Calculators by compound

RetatrutideVial, water and weekly dose to syringe units TirzepatideThe 2.5 to 15 mg ladder, converted SemaglutideThe 0.25 to 2.4 mg ladder, converted BPC-157mcg doses from a 5 or 10 mg vial ReconstitutionHow much water to add, and why it matters Dosing chartsPrintable unit tables for every compound Titration schedulesFull ladders with units at every step Reading a syringeU-100 vs U-40, and the 2.5x error How much water?Pick a volume that lands where you can read it

Common questions

How many units is 0.25 mg of semaglutide?: In a 5 mg vial with 2 mL of water the concentration is 2.5 mg/mL, so 0.25 mg is 0.1 mL, which is 10 units on a U-100 syringe.
How much bacteriostatic water for a 5 mg semaglutide vial?: 2 mL is the common choice and gives 2.5 mg/mL. That places the 0.25 to 2.4 mg ladder between 10 and 96 units, which fits a 1 mL syringe across the whole range.
Why are my units different from someone else's?: Because they used a different amount of water. Units are only meaningful alongside the vial strength and the water volume. Always state all three.
How many doses in a 10 mg vial?: Divide 10 by your weekly dose. At 0.5 mg that is 20 doses, or 140 days.

Read this before you use the numbers. This is a unit-conversion tool. It converts a vial strength and a volume of bacteriostatic water into a concentration, a draw volume and a mark on an insulin syringe. It does not tell you what to take, whether to take it, or whether a compound is safe for you. Most of the compounds listed here are sold for laboratory research use and are not approved for human use. Nothing on this site is medical advice. Dosing decisions belong with a licensed clinician who knows your history. Always confirm the strength printed on your own vial rather than trusting a preset.