To be frank, market rate is however little your employer thinks they can get away with paying you, or someone comparable to you. Look at indeed.com and salary.

To be frank, market rate is however little your employer thinks they can get away with paying you, or someone comparable to you. Look at indeed.com and salary.com and aim for 75th percentile and higher. Unfortunately the only way to really know is to put yourself out there and see what offers you get.