Wegovy vs Mounjaro: cost and weight loss calculator
How much weight will you lose with Wegovy or Mounjaro? And how much will it cost? Use our handy interactive calculator to find out.
Are you interested in losing weight using the injectable medications Wegovy or Mounjaro?
If so, you might be wondering just how much weight you can expect to lose and how much it will cost to lose it.
The short answer is that Mounjaro tends to yield more weight loss but is more expensive:
- Mounjaro users lose an average of 21% with diet changes and exercise.¹ With SemaPen, it starts at £225 per dose.
- Wegovy users lose an average of 15% with diet changes and exercise.² With SemaPen, it starts at £189 per dose.
But this doesn't tell you the full story. The prices change as you work through our Wegovy and Mounjaro Programmes. And what 21% weight loss means for one person could be very different for another person.
That's why we've created this handy weight loss and cost calculator to help you compare Wegovy and Mounjaro.
Mounjaro vs Wegovy calculator
How can the calculator help me compare Wegovy and Mounjaro?
The calculator shows you how much weight you can expect to lose after 12 months of taking Wegovy or Mounjaro.
This is handy if you need a quick weight loss estimate. But it gets really useful when you consider price, too.
Our calculations factor in the full cost of Wegovy and Mounjaro across each programme, even as prices change when doses increase.
That means you can see exactly what you'll pay over 12 months, plus the cost of each pound or kilogramme lost.
So, while Mounjaro typically yields more weight loss, it might not offer the best value for you. It all depends on your starting weight. Let's look at an example.
An example
Let's say you weigh 150kg (just under 24 stone). Using the calculator, you can see you'd lose:
- A total of 23kg with Wegovy, at a cost of £94.13 per kilogramme
- A total of 30kg with Mounjaro, at a cost of £111.16 per kilogramme
- An extra 7kg is nothing to sniff at. And it would only cost you an extra £17.53 per kilo. Nice!
- But things look different with a lower starting weight. If you start at 90kg (about 14 stone), you can expect to lose:
- A total of 14kg on Wegovy, at a cost of £154.63 per kilogramme
- A total of 18kg on Mounjaro, at a cost of £186.10 per kilogramme
- In this scenario, you're losing an extra 4kg with Mounjaro, which isn't bad at all. However, the cost difference now stands at £31.47 per kilo.
These are the kinds of pros and cons you'll need to weigh up when choosing between Wegovy or Mounjaro. We hope our calculator makes it a little easier to decide.
How are the results calculated?
We've based our calculations on the average weight loss for Wegovy (15%)² and Mounjaro (21%),¹ as seen in clinical trials. The prices are based on the cost of each drug over a 12-month course of treatment with SemaPen. Prices are correct as of 18 September 2025.
Still need help choosing the best weight loss medication for you? Check out our guide to the differences between Wegovy and Mounjaro.
Ready to take the next step towards safe, steady weight loss? Take our online consultation and you'll find out today if you're eligible for treatment.
Sources
1. Jastreboff, A.M. et al. (2022) "Tirzepatide Once Weekly for the Treatment of Obesity" The New England Journal of Medicine, 387(3) https://doi.org/10.1056/NEJMoa2206038
2. Wilding, J.P.H. et al. (2021) "Once-weekly semaglutide in adults with overweight or obesity" The New England Journal of Medicine, 384(11) https://doi.org/10.1056/NEJMoa2032183
