Semaglutide Dosage Calculator

This semaglutide dosage calculator is about the powder vials. Most semaglutide pages are about pens; here you add the water yourself and the strength of the mix is yours to get right. Enter the vial, the water and your dose, and get the exact draw in units.

Results update automatically as you type.

On this page

Powder vials are not pens

A pen arrives pre-mixed. The manufacturer set the strength, and the dose window or click count on the pen belongs to that strength and no other. A powder vial arrives dry. Its strength does not exist until you add water, and it is whatever your water amount makes it: a 5 mg vial in 1 mL is a 5 mg per mL mix, and the same vial in 2 mL is a 2.5 mg per mL mix.

That is why pen numbers never carry over. A dose that is one setting on a pen is 10 units from one powder mix and 5 units from another, and both are correct. If you are working with powder, the only safe route is your own vial, your own water amount, and the maths done on those two numbers. That is all this page does.

Semaglutide dosage calculator table: 5 mg vial, 2 mL of water

This mix is 2.5 mg per mL. Semaglutide doses are small, so the draws are small too, and this is the mix where they land on round, readable numbers.

Dose	Draw in units	Draw in mL
0.25 mg	10 units	0.1 mL
0.5 mg	20 units	0.2 mL
0.75 mg	30 units	0.3 mL
1 mg	40 units	0.4 mL
1.5 mg	60 units	0.6 mL
2 mg	80 units	0.8 mL

Concentration for the common semaglutide mixes

Vial	With 1 mL of water	With 2 mL of water	With 3 mL of water
5 mg	5 mg/mL	2.5 mg/mL	1.67 mg/mL
10 mg	10 mg/mL	5 mg/mL	3.33 mg/mL
15 mg	15 mg/mL	7.5 mg/mL	5 mg/mL

Bigger vial or a different amount of water? The main peptide calculator handles any combination, and the dosage chart has the standard mixes as printable tables.

Common questions

How many units is 0.25 mg of semaglutide?

In the most common mix, a 5 mg vial with 2 mL of water, the concentration is 2.5 mg per mL and 0.25 mg is exactly 10 units. Mix the same vial with 1 mL instead and it is 5 units, because the mix is twice as strong. The number only means anything with the mix attached to it.

Is 0.25 mg the same as 250 mcg?

Yes, exactly the same amount. There are 1,000 micrograms in a milligram, so 0.25 mg is 250 mcg. Semaglutide gets written both ways depending on the source, and mixing the two up is a 1,000 times error, which is why the calculator accepts either unit and shows your dose back to you in both.

How much BAC water do I add to a 5 mg semaglutide vial?

Your choice. 2 mL is the worked example on this page because it makes the small doses land on round numbers: 0.25 mg is 10 units, 0.5 mg is 20 units. 1 mL makes every draw half the size, which gets fiddly at these amounts. The calculator works with any amount you type in.

Can I use pen dose numbers with a powder vial?

No. A pen holds a ready-mixed liquid at a strength set by the manufacturer, and its clicks or markings belong to that strength only. A powder vial is mixed by you, at whatever strength your water amount makes. The same dose is a different volume in the two products, so numbers from one do not transfer to the other. This page is only about powder vials.

How many doses are in a 10 mg vial?

It depends on the dose. At 0.5 mg a dose, 20 doses. At 1 mg a dose, 10 doses. The water amount does not change the count, only the size of each draw. The calculator shows the count for your numbers, including any leftover too small to be a full dose.

Arithmetic only

This calculator does maths on the numbers you enter. It works out concentration, draw volume and syringe units from the vial amount and water volume you give it. Nothing more.

It does not recommend amounts, schedules or products, and it does not know what is in your vial. It uses the amount printed on the label. If the label and the actual contents differ, the result differs too. For medical questions, talk to a clinician.

How the maths works, and where the facts on this site come from: Methodology and sources.