The rule that explains everything below
- ~0.01 ml
- what one click advances on essentially every pen here
- ~1 unit
- the same volume on a U-100 insulin syringe
- 6
- different concentrations across the pens in this chart
- 0
- manufacturers who endorse dosing this way
One click is about a hundredth of a millilitre, which is one unit on a standard U-100 syringe. That is remarkably consistent across the whole category. What is not consistent is what a hundredth of a millilitre contains, because these pens run from 0.68 mg/ml up to 6 mg/ml.
So: a click is a volume. Milligrams follow the concentration. Everything confusing about click counts dissolves once that is fixed in place.
Semaglutide: four Ozempic pens, three concentrations
| Pen | Concentration | Full dial | Clicks to full dial | One click is |
|---|---|---|---|---|
| Ozempic 0.25 / 0.5 mg (3 ml) | 0.68 mg/ml | 0.5 mg | 72 | ~0.007 mg |
| Ozempic 0.25 / 0.5 mg (1.5 ml, older) | 1.34 mg/ml | 0.5 mg | 36 | ~0.014 mg |
| Ozempic 1 mg | 1.34 mg/ml | 1 mg | 72 | ~0.014 mg |
| Ozempic 2 mg | 2.68 mg/ml | 2 mg | 72 | ~0.028 mg |
All four hold four labelled doses and are labelled for 56 days of use once started.
Look at the first two rows, because that is the whole problem in one place. Both pens say “0.25 / 0.5 mg” on the box. The 1.5 ml version, phased out from 2023 but still in circulation, is twice as concentrated as the 3 ml pen sold today. The same 0.25 mg is 36 clicks on one and 18 on the other.
Anybody quoting a click count for “the Ozempic starter pen” without saying which one is quoting a number that is right half the time. In practice, on the pens sold today:
| Dose | 0.25 / 0.5 pen (3 ml) | 1 mg pen | 2 mg pen |
|---|---|---|---|
| 0.25 mg | 36 | 18 | – |
| 0.5 mg | 72 | 36 | 18 |
| 0.75 mg | – | 54 | – |
| 1 mg | – | 72 | 36 |
| 1.5 mg | – | – | 54 |
| 2 mg | – | – | 72 |
Approximate, rounded, and dependent on the exact pen in your hand. Tracking Ozempic explains why Penwise asks which pen you have.
Tirzepatide: one volume, six meanings
The KwikPen works differently. It has no dose dial – the strength is decided by which box you were dispensed, and the device delivers one fixed 0.6 ml shot. Sixty clicks make up that full dose on every strength, so the click count is identical and the milligrams are not.
| KwikPen strength | Full dose | Clicks to full dose | One click is |
|---|---|---|---|
| 2.5 mg | 0.6 ml | 60 | ~0.042 mg |
| 5 mg | 0.6 ml | 60 | ~0.083 mg |
| 7.5 mg | 0.6 ml | 60 | ~0.125 mg |
| 10 mg | 0.6 ml | 60 | ~0.167 mg |
| 12.5 mg | 0.6 ml | 60 | ~0.208 mg |
| 15 mg | 0.6 ml | 60 | ~0.25 mg |
Mounjaro and Zepbound KwikPens are identical devices. Both hold four doses and are labelled for 30 days of use once started.
This is where a number copied from a forum does the most damage: “60 clicks” is correct on every KwikPen and tells you nothing about the dose, because a click on a 15 mg pen carries six times what a click on a 2.5 mg pen does. The single-use tirzepatide pens have no dial at all and are not click-dosable in any sense.
Wegovy FlexTouch: every strength is its own concentration
The four-dose FlexTouch sold outside the US changes both the volume and the concentration as the strength goes up, which makes it the least transferable of the lot.
| Strength | Volume per dose | Clicks to full dose | One click is |
|---|---|---|---|
| 0.25 mg | 0.37 ml | 37 | ~0.007 mg |
| 0.5 mg | 0.37 ml | 37 | ~0.014 mg |
| 1 mg | 0.75 ml | 75 | ~0.013 mg |
| 1.7 mg | 0.75 ml | 75 | ~0.023 mg |
| 2.4 mg | 0.75 ml | 75 | ~0.032 mg |
The single-dose Wegovy pen has no dial and delivers its whole contents in one shot.
Liraglutide: the one that is actually consistent
Saxenda and Victoza are both 18 mg in 3 ml – 6 mg/ml – so a click is worth the same on both, and it works out to a round number.
| Dose | Saxenda | Victoza |
|---|---|---|
| 0.6 mg | 10 clicks | 10 clicks |
| 1.2 mg | 20 clicks | 20 clicks |
| 1.8 mg | 30 clicks | 30 clicks |
| 2.4 mg | 40 clicks | – |
| 3.0 mg | 50 clicks | – |
One click is about 0.06 mg on both. Victoza dials to 1.8 mg, Saxenda to 3.0. Both are daily – see tracking Saxenda and Victoza.
Compounded vials, where there is no dial at all
With a vial and a syringe the click question disappears and a different one replaces it: how many units is my dose. The arithmetic is the same idea in reverse – you know the concentration, you want a dose, the syringe is graduated in volume.
A 10 mg / 1 ml tirzepatide vial is 10 mg/ml, so 1 unit of a U-100 syringe (0.01 ml) is 0.1 mg. A 5 mg / 2 ml semaglutide vial is 2.5 mg/ml, so 1 unit is 0.025 mg. Penwise carries five vial presets and lets you enter your own concentration, converting in both directions so the number you draw up is not one you did in your head at the counter.
Why Penwise stores clicks per dose rather than clicks per milligram
This is a design decision worth explaining, because it is the reason the app gets pens right where a spreadsheet does not.
Penwise stores, for each pen, how many clicks make up one full labelled dose. It never stores a clicks-per-milligram figure, because that number is not a property of the pen – it is a property of the pen and the strength together. Storing it the other way is exactly how two pens labelled the same end up sharing one wrong number.
Everything else follows: the app knows the concentration of the pen you told it you have, so it converts between clicks, millilitres, units and milligrams without you memorising anything. And because it knows the labelled doses and the in-use window, it can also tell you when your plan outlasts the pen – see how long a GLP-1 pen lasts.
Stop looking up click counts
Seventeen pens and five vial presets, each with its own arithmetic. Free core tracker, no account.
Common questions
How many clicks is one dose on a Mounjaro KwikPen?
How many clicks is 0.25 mg of Ozempic?
Is one click the same as one unit on a syringe?
Do manufacturers approve of counting clicks?
Why does the same click count give a different dose on two pens with the same label?
Does Penwise do the conversion for compounded vials too?
Sources
Every factual claim on this page traces to the product information a regulator publishes, or to a published trial. Links open on the site of whoever issued the document.
- Mounjaro: EPAR product information European Medicines Agency
- Ozempic: EPAR product information European Medicines Agency
- Wegovy: EPAR product information European Medicines Agency
Penwise is a tracking and education tool, not a medical device. Nothing on this page is medical advice, a diagnosis or a recommendation to start, stop or change a dose. Dosing decisions belong to you and your clinician. Ozempic, Wegovy, Rybelsus, Saxenda and Victoza are trademarks of Novo Nordisk; Mounjaro, Zepbound and Trulicity are trademarks of Eli Lilly. Penwise is not affiliated with, endorsed by or connected to either company.