It might be that you can sometimes get a higher salary than advertised but they values are provided directly by the companies posting the jobs and they seem in the range of PayScale: https://www.payscale.com/research/CH/Job=Software_Engineer/S...
In the end you can find a Senior earning 250k CHF annually and one earning 100k, there are many factors that come into play.
It's also important to consider both salaries and costs of living but I would say from my 2 year experience here that you can live better than in Silicon Valley and save in the same time.