Pen click dashboard
Exact click counts, doses per pen, supply length and cost per dose. For every UK pen strength.
How the Mounjaro click maths works
The UK KwikPen is a multi-dose pen with a precisely calibrated dial. Three facts unlock everything else:
- One full labelled dose = 60 clicks = 0.6 ml. That is true for every strength, from 2.5 mg to 15 mg.
- The volume never changes. The concentration does. A 60-click injection from a 2.5 mg pen and a 15 mg pen delivers the same 0.6 ml of fluid; the 15 mg pen simply contains tirzepatide at six times the concentration.
- Clicks scale linearly. 30 clicks from a 10 mg pen delivers 5 mg; 15 clicks delivers 2.5 mg. The maths is simple, but any dose that isn't the printed label is off-label, and that's a prescriber conversation, not a DIY decision.
KwikPen V1 vs V2: why the fifth dose disappeared
| Legacy V1 pen | Current V2 pen | |
|---|---|---|
| Total fluid | 3.2 ml | 2.6 ml |
| Labelled doses | 4 × 0.6 ml | 4 × 0.6 ml |
| Total clicks available | ~300 | ~240 |
| "Fifth dose" | Physically possible (60 extra clicks of overfill) | Not possible. The fluid simply isn't there |
Eli Lilly redesigned the UK pen so that four labelled doses use essentially all the fluid. If you have seen videos or forum posts about extracting a fifth dose, they almost certainly refer to the old V1 pen, and even then, extracting overfill was never part of the licensed instructions. Our fifth dose guide covers the full history and the safety picture.
Quick reference: clicks for common doses
| Pen strength | Full dose (60 clicks) | 30 clicks | 45 clicks |
|---|---|---|---|
| 2.5 mg | 2.5 mg | 1.25 mg | 1.88 mg |
| 5 mg | 5 mg | 2.5 mg | 3.75 mg |
| 7.5 mg | 7.5 mg | 3.75 mg | 5.63 mg |
| 10 mg | 10 mg | 5 mg | 7.5 mg |
| 12.5 mg | 12.5 mg | 6.25 mg | 9.38 mg |
| 15 mg | 15 mg | 7.5 mg | 11.25 mg |
Counting clicks to deliver anything other than your prescribed, labelled dose is off-label use. People do it to taper between strengths or stretch pens, and we understand why. But dosing outside your prescription carries real risks. Think dosing errors, contamination, and side effects your prescriber hasn't planned for. Always agree any non-standard dose with the clinician who prescribed it.
Getting honest about cost per dose
UK private Mounjaro prices vary widely between pharmacies, and the "headline" monthly price often hides consultation fees, delivery charges and price rises at higher strengths. Enter what you actually paid above and the calculator divides it by your real number of doses. Comparing providers on cost per dose (rather than per month) is the only like-for-like comparison. Monj.co.uk manually verifies UK Mounjaro pharmacies (including their pricing transparency) before listing them, which saves you the spreadsheet work.
Frequently asked questions
How many clicks are in a full Mounjaro dose? +
Exactly 60 clicks, on every UK KwikPen strength. The fluid volume per injection is always 0.6 ml; the pen strength changes the concentration of tirzepatide in that fluid, not the number of clicks.
What is the difference between KwikPen V1 and V2? +
The legacy V1 pen held 3.2 ml (~300 clicks), leaving enough overfill after four doses for a "fifth dose". The current V2 pen holds 2.6 ml (~240 clicks). Four doses use almost all the fluid, so there is no usable fifth dose.
Can I use clicks to take a smaller dose than my pen is labelled for? +
Mathematically yes. Clicks scale linearly, so 30 clicks of a 10 mg pen delivers 5 mg. But that is off-label use, and it should only ever happen with your prescriber's explicit agreement. This calculator explains the arithmetic; it does not recommend doing it.
How long does one Mounjaro pen last? +
At your labelled dose, four weeks (four weekly injections). If you and your prescriber agree a smaller click-counted dose, a pen lasts proportionally longer. Enter your dose above to see the exact figure.
Does the calculator work for Wegovy and Ozempic too? +
Yes. Switch tabs in the dashboard. Wegovy FlexTouch pens and Ozempic pens use different concentrations and click volumes (1 click = 0.01 ml), which the calculator handles automatically. We also have dedicated Wegovy and Ozempic calculator pages.
References & official sources
Show all 5 cited sources, with study authors +
- electronic medicines compendium. Mounjaro KwikPen SmPC & patient leaflet: www.medicines.org.uk/emc/search?q=mounjaro
- Eli Lilly UK. Mounjaro KwikPen storage, transport and travel guidance: medical.lilly.com/uk/products/answers/how-should-patients-store-the-mounjaro-tirzepatide-kwikpen-during-transport-and-travel-217602
- NICE TA1026. Tirzepatide for managing overweight and obesity: www.nice.org.uk/guidance/ta1026
- MHRA. Yellow Card reporting scheme: yellowcard.mhra.gov.uk/
- GPhC. Check a pharmacy registration: www.pharmacyregulation.org/registers