How much is it to get a electrical tester calibrated?

what kind of tester is it,if its less than a year old shouldn't cost anything, i'm kinda curious though,is it digital,how do you calibrate a digital meter? now if its og i can see that,and there's a set screw on the dial that lets you calibrate it,not sure how you would calibrate a digital one i thought all the calibration was set up in the program that is on the chip,at least that's the way my klein is setup