I’m often asked ‘how many hair removal sessions will I need using laser or IPL?’ This is not an easy question to answer because it depends on a high number of variables including your equipment, your training and, of course, your patient/client.
But, I have tried to answer this question using a computer model of the hair growth cycles across the body.
Body Area | Duration of Anagen (weeks) | % Anagen | Duration of Telogen (weeks) | % Telogen |
Chin | 52 | 81 | 10 | 16 |
Upper Lip | 8-20 | 43-71 | 6 | 43-21 |
Armpits | 16 | 53 | 12 | 40 |
Bikini | 16 | 53 | 12 | 40 |
Legs & Thighs | 16 | 42 | 20 | 53 |
The table above shows the variation in anagen and telogen phases across the body, in weeks. These timings are important when considering hair removal because they directly affect the number of sessions you might need. Light-based treatments, such as laser or IPL, can only destroy the follicles when they are in anagen phase.
My model allowed me to find out when the ‘optimum’ times were to carry out sessions. I based this on detecting when most of the follicles were back in anagen after a treatment session.
Here’s what I found:
Interval (weeks) | Chin | Upper Lip | Armpits | Bikini | Legs & Thighs |
4 | 7 | 7 | 8 | 8 | 9 |
6 | 6 | 7 | 7 | 7 | 8 |
8 | 6 | 6 | 6 | 6 | 7 |
If you treat someone every four weeks, then the table above shows how many sessions you will need (at a minimum) to achieve an excellent result. On all body areas, you will need between 7 and 9 sessions, in total.
If you treat every six weeks, then the total number reduces to between 6 and 8. If you do sessions every eight weeks, then the total number required drops to between 6 and 7.
So, this means that it doesn’t make much difference at all!! But, this analysis does show that
leaving longer gaps between sessions, will reduce the total number needed!
In reality, the total number of treatments will also depend on how good your equipment and training are. You can have the best laser/IPL in the world, but if you don’t know how to use it properly, you will always struggle to get good results!

We will be discussing this topic, and many others, in our MasterClass in Birmingham later this year. Click on the above image to learn more.
Hope this helps,
Mike.
