Problem
You are running a company with nice employees. You raise the salaries often. But you are not sure how much you have to raise the salaries.
If the salaries are too low people will quit, and you will not be able to hire replacements for the same amount of money.
Solution
There's a nice tool from Stack Overflow where you can find salaries for jobs in IT: https://stackoverflow.com/jobs/salary/results
It still does not answer the exact amount of money you should pay. But you can see the percentiles. If your people are good then you should likely pay them in the 50 to 75 percentile.