GLP-1 mg to units calculator: convert insulin syringe units to mg
For planning and record-keeping only — not medical advice. Your dose and schedule are set by your prescriber.
If the question is how many units is 2.5 mg, the answer is 25 units on a U-100 insulin syringe at a vial concentration of 10 mg/mL — and 50 units at 5 mg/mL, because units measure volume rather than milligrams. Read the same scale backwards and 20 units at 10 mg/mL is 2 mg, while those same 20 units at 5 mg/mL are 1 mg. This converter runs both conversions for any dose and any mg/mL — and, if you're starting from a dry vial and bacteriostatic water, works out the concentration first.
Mg to units converter
Use this half when the concentration is already known — it's printed on the label of a pre-mixed vial, or you calculated it below. Both fields are required; the result shows insulin syringe units and the volume they correspond to.
Convert a dose to syringe units
Mg to units
0 units = 0 mL on a U-100 syringe
More than 100 units — that volume doesn't fit a single 1 mL U-100 syringe.
Double-check with your pharmacist — a misread concentration changes the entire calculation.
Enter positive numbers only — zero or negative values can't be converted.
Units to mg
0 mg = 0 mL on a U-100 syringe
More than 100 units — that volume doesn't fit a single 1 mL U-100 syringe.
Double-check with your pharmacist — a misread concentration changes the entire calculation.
Enter positive numbers only — zero or negative values can't be converted.
Insulin units to mg
The same syringe read in the other direction. Enter the mark you are looking at and the concentration on the vial, and the second panel above returns the milligrams that volume of liquid holds. Which milligram figures a label actually names is a separate question — the tirzepatide dosage chart and the semaglutide dosage chart list the strengths on each.
mg = units ÷ 100 × (mg/mL)
If your vial started dry
A powder vial has no concentration until you add water, so there is nothing to convert yet. Enter the milligrams printed on the vial and the millilitres you added, and this panel returns the mg/mL — feed that back into either converter above. Choosing the water volume in the first place is a different question, and the reconstitution calculator is built for it: it works backwards from the unit count you want per dose.
0 mg/mL after reconstitution
Your dose: 0 units (0 mL)
More than 100 units — that volume doesn't fit a single 1 mL U-100 syringe.
Double-check with your pharmacist — a misread concentration changes the entire calculation.
Enter positive numbers only — zero or negative values can't be converted.
units = mg ÷ (mg/mL) × 100
KeepAlong — GLP-1 shot tracker & planning tools
There's no dose calculator inside the KeepAlong app — Apple's health guidelines rule that out, so the math stays here on the web. What the app does is log every injection with its dose and remind you when the next shot is due.
The app is launching soon. The web tools on this site are free — no sign-up needed.
Low doses converted to units: 0.25 to 2.4 mg
Every conversion on this page assumes a standard U-100 insulin syringe — 100 units per milliliter, the scale described in the NIH overview of insulin syringes (checked 2026-08-18). This first table covers the milligram range semaglutide is dosed in, so the concentrations beside it are low ones: 1 mg/mL is a 1 mg vial in 1 mL of water, 2 mg/mL is a 5 mg vial in 2.5 mL, 2.5 mg/mL is that 5 mg vial in 2 mL, and 5 mg/mL is the same vial in 1 mL. The four are here to show the range, not because anyone recommends them. If your question is how many units is 1.7 mg, the row is here — 34 units at 5 mg/mL, 68 units at 2.5 mg/mL.
Not every row is a label step. The approved semaglutide ladder runs 0.25, 0.5, 1, 1.7 and 2.4 mg; 1.25 and 1.5 mg sit between those steps and are in the table because the conversion is asked for, not because a label names them.
| Dose | At 1 mg/mL | At 2 mg/mL | At 2.5 mg/mL | At 5 mg/mL |
|---|---|---|---|---|
| 0.25 mg | 25 units (0.25 mL) | 12.5 units (0.13 mL) | 10 units (0.1 mL) | 5 units (0.05 mL) |
| 0.5 mg | 50 units (0.5 mL) | 25 units (0.25 mL) | 20 units (0.2 mL) | 10 units (0.1 mL) |
| 1 mg | 100 units (1 mL) | 50 units (0.5 mL) | 40 units (0.4 mL) | 20 units (0.2 mL) |
| 1.25 mg | 125 units (1.25 mL)* | 62.5 units (0.63 mL) | 50 units (0.5 mL) | 25 units (0.25 mL) |
| 1.5 mg | 150 units (1.5 mL)* | 75 units (0.75 mL) | 60 units (0.6 mL) | 30 units (0.3 mL) |
| 1.7 mg | 170 units (1.7 mL)* | 85 units (0.85 mL) | 68 units (0.68 mL) | 34 units (0.34 mL) |
| 2 mg | 200 units (2 mL)* | 100 units (1 mL) | 80 units (0.8 mL) | 40 units (0.4 mL) |
| 2.4 mg | 240 units (2.4 mL)* | 120 units (1.2 mL)* | 96 units (0.96 mL) | 48 units (0.48 mL) |
* Over 100 units, so that volume doesn't fit one 1 mL U-100 syringe in a single draw.
Higher doses converted to units: 2.5 to 30 mg
The milligram range tirzepatide is dosed in needs higher concentrations to stay inside one syringe, so the columns change: 5 mg/mL is a 5 mg vial reconstituted with 1 mL of water; 10 mg/mL is 10 mg + 1 mL or a 17 mg vial + 1.7 mL; 17 mg/mL is that same 17 mg vial + 1 mL; 20 and 30 mg/mL are here because no lower column keeps the largest rows inside one 1 mL draw — 20 mg reaches exactly 100 units at 20 mg/mL, and 30 mg only at 30 mg/mL. Same vial, different water volume, different concentration — which is why the mg/mL figure matters more than the number on the vial, and why one mg to unit conversion lands on five different marks across a row.
The approved tirzepatide ladder stops at 15 mg. The 20, 25 and 30 mg rows are arithmetic for people who arrive with those figures in hand, not label steps, and a conversion appearing in a table says nothing about whether the dose belongs in a prescription.
| Dose | At 5 mg/mL | At 10 mg/mL | At 17 mg/mL | At 20 mg/mL | At 30 mg/mL |
|---|---|---|---|---|---|
| 2.5 mg | 50 units (0.5 mL) | 25 units (0.25 mL) | 14.7 units (0.15 mL) | 12.5 units (0.13 mL) | 8.3 units (0.08 mL) |
| 4 mg | 80 units (0.8 mL) | 40 units (0.4 mL) | 23.5 units (0.24 mL) | 20 units (0.2 mL) | 13.3 units (0.13 mL) |
| 5 mg | 100 units (1 mL) | 50 units (0.5 mL) | 29.4 units (0.29 mL) | 25 units (0.25 mL) | 16.7 units (0.17 mL) |
| 7.5 mg | 150 units (1.5 mL)* | 75 units (0.75 mL) | 44.1 units (0.44 mL) | 37.5 units (0.38 mL) | 25 units (0.25 mL) |
| 10 mg | 200 units (2 mL)* | 100 units (1 mL) | 58.8 units (0.59 mL) | 50 units (0.5 mL) | 33.3 units (0.33 mL) |
| 12 mg | 240 units (2.4 mL)* | 120 units (1.2 mL)* | 70.6 units (0.71 mL) | 60 units (0.6 mL) | 40 units (0.4 mL) |
| 12.5 mg | 250 units (2.5 mL)* | 125 units (1.25 mL)* | 73.5 units (0.74 mL) | 62.5 units (0.63 mL) | 41.7 units (0.42 mL) |
| 15 mg | 300 units (3 mL)* | 150 units (1.5 mL)* | 88.2 units (0.88 mL) | 75 units (0.75 mL) | 50 units (0.5 mL) |
| 20 mg | 400 units (4 mL)* | 200 units (2 mL)* | 117.6 units (1.18 mL)* | 100 units (1 mL) | 66.7 units (0.67 mL) |
| 25 mg | 500 units (5 mL)* | 250 units (2.5 mL)* | 147.1 units (1.47 mL)* | 125 units (1.25 mL)* | 83.3 units (0.83 mL) |
| 30 mg | 600 units (6 mL)* | 300 units (3 mL)* | 176.5 units (1.76 mL)* | 150 units (1.5 mL)* | 100 units (1 mL) |
* More than one full 1 mL U-100 syringe — a single draw can't hold that volume.
Unit counts converted to mg: 2 to 100 units
Three concentrations, read from the syringe mark instead of the prescription — this is the table to use when you know how many units you drew and want the milligrams. The millilitres in the first column are fixed by the U-100 scale and never change; the milligrams those millilitres hold change with every concentration, which is why one unit count sits against three different doses across the row.
| Units drawn | At 5 mg/mL | At 10 mg/mL | At 17 mg/mL |
|---|---|---|---|
| 2 units (0.02 mL) | 0.1 mg | 0.2 mg | 0.34 mg |
| 4 units (0.04 mL) | 0.2 mg | 0.4 mg | 0.68 mg |
| 7.5 units (0.075 mL) | 0.375 mg | 0.75 mg | 1.275 mg |
| 10 units (0.1 mL) | 0.5 mg | 1 mg | 1.7 mg |
| 15 units (0.15 mL) | 0.75 mg | 1.5 mg | 2.55 mg |
| 20 units (0.2 mL) | 1 mg | 2 mg | 3.4 mg |
| 25 units (0.25 mL) | 1.25 mg | 2.5 mg | 4.25 mg |
| 30 units (0.3 mL) | 1.5 mg | 3 mg | 5.1 mg |
| 40 units (0.4 mL) | 2 mg | 4 mg | 6.8 mg |
| 48 units (0.48 mL) | 2.4 mg | 4.8 mg | 8.16 mg |
| 50 units (0.5 mL) | 2.5 mg | 5 mg | 8.5 mg |
| 60 units (0.6 mL) | 3 mg | 6 mg | 10.2 mg |
| 75 units (0.75 mL) | 3.75 mg | 7.5 mg | 12.75 mg |
| 100 units (1 mL) | 5 mg | 10 mg | 17 mg |
A number in this table is arithmetic, not an instruction — what your vial holds is the mg/mL on its own label, and your pharmacist is the one to confirm it against your prescription.
Who actually needs this math
People injecting from a vial. Compounded semaglutide and tirzepatide are typically dispensed in vials — either pre-mixed liquid with the mg/mL on the label, or a dry powder you reconstitute yourself — and drawn up with a U-100 insulin syringe. That workflow has no dose dial, so converting milligrams to syringe units falls to you and your pharmacist. The guides to tracking semaglutide and tracking tirzepatide cover how units fit into the weekly log alongside milligrams, and compounded tirzepatide dosage lays out the approved steps in units across the concentrations compounded vials come in.
What decides it is the form, not the brand. A pen meters the volume itself — you dial or click the labeled dose and the device delivers it — so a pen workflow has nothing to convert, whether the pen is a single-dose Wegovy or Ozempic pen, a multi-dose FlexTouch, or a KwikPen. The prefilled single-dose syringes on the semaglutide labels come filled to their dose too, which is a different object from an empty U-100 syringe and a vial. A vial has no dose dial, which is why the tirzepatide labels tell patients using vials to use a syringe capable of measuring the dose and a new syringe and needle for every injection. Mounjaro and Zepbound are each supplied as single-dose vials in all six strengths and as multi-dose vials holding four doses, next to their pens — Zepbound's vials are one example of that split, and being on a brand-name product says nothing on its own about whether syringe math is part of your week.
One difference still separates the two kinds of vial. A branded vial's label names the volume for each dose — 0.5 mL from a single-dose vial, 0.6 mL from a multi-dose one, which on a U-100 scale is 50 and 60 units — so there is a stated number to draw to. A compounded vial hands you a concentration instead and leaves the volume to be worked out, and that is the case this calculator is built for.
This page converts a prescribed dose into syringe marks, and that's all it does. Which dose belongs to which week is a titration question — the titration schedule planner turns the label ladders into calendar dates — and what results to expect is what the weight loss calculator estimates from trial data. Once the dose is drawn, the recurring problem is remembering the next one: that's the job of the GLP-1 shot tracker app.
Frequently asked questions
How many units is 1 mg?
At 1 mg/mL, 1 mg is 100 units — a full 1 mL insulin syringe. At 2 mg/mL the same 1 mg is 50 units, at 2.5 mg/mL it is 40 units, and at 5 mg/mL it is 20 units. Units measure volume, so the mg/mL printed on your vial sets the mark: units = mg ÷ (mg/mL) × 100.
How many units is 2.5 mg?
At 10 mg/mL, 2.5 mg is 25 units on a U-100 insulin syringe. At 5 mg/mL the same 2.5 mg is 50 units, at 17 mg/mL it is 14.7 units, and at 20 mg/mL it is 12.5 units. Nothing changes but the concentration — the milligrams drawn are identical.
How many mg is 20 units?
Twenty units is 0.2 mL on a U-100 insulin syringe, which holds 1 mg at 5 mg/mL, 2 mg at 10 mg/mL, and 3.4 mg at 17 mg/mL. Units measure volume, not milligrams, so without the concentration the question has no single answer: mg = units ÷ 100 × (mg/mL).
How do you convert mg to units on an insulin syringe?
Divide the milligrams by the concentration in mg/mL and multiply by 100. A 1 mg dose from a 1 mg/mL vial is 100 units, the whole 1 mL syringe; 10 mg from a 10 mg/mL vial is also 100 units. The drug never enters the arithmetic — only volume does.
What does U-100 mean on an insulin syringe?
U-100 means the syringe scale assumes 100 units per milliliter, so one unit is 0.01 mL and a full 1 mL syringe holds 100 units. That is why units equal mL × 100 for any liquid drawn into it — the marks measure volume, regardless of what the liquid is.
Does a units calculator apply to a pen?
No — a pen meters the volume itself, so a 0.25 mg or 2.4 mg dose arrives from the dial with no unit count to draw to. A branded vial’s label names the volume per dose too. This page is for vials that state only a concentration; ask your pharmacist if the mg/mL is unclear.
KeepAlong is an independent app and website. Not affiliated with, endorsed by, or sponsored by Novo Nordisk or Eli Lilly.