The last piece of information that you need is to know comparable salaries for your position at similar companies. There are some good online resources to start with: Salary.com and Payscale.com. These sites allow you to define your job responsibilities and your skills and location and they return a salary range and benefits like bonuses. They have both free and premium services. You may only need the free service. Glassdoor.com is a site where employees anonymously post their titles and pay so you can see what a Software Engineer II makes at IBM, for example. If you belong to an alumni association or can still use your college career center, they will have useful information too.
Be honest with yourself when you use these salary comparisons. Small differences in responsibilities or differences in locations can have a big impact. Use a couple of resources to try to get the best estimate you can.
