Salary is not freely available, you generally have to pay for specific lookups as a private person.

However there is a lowtech way around this. Taxed income is published yearly in a book that resembles an old phonebook, Taxeringskalendern ("the tax calendar"). Freedoom of the press, see?

This book (or the part of the book that covers your region) will be available at your local library in the "reference" section. For most people you take the number from the book and divide by 12 and you have a lower bound of their monthly salary. Unless they are stalking you at the library noone will know. Very useful when going into salary negotiotiations to know aprox what the rest of the team and your boss makes.