If you can't find the probable compensation on Glassdoor, Indeed, etc. for the position, I've found that the best way to answer this question is to respond with a range and some wording like, "I make in the $_ 0, 000's, which is a fair wage for my current position, however I'm obviously looking to advance my career goals both professionally and financially. I am confident when you choose me as the top candidate, the company will extend to me its best offer that is competitive based on the market and fair with regard to my skills and qualifications."