How do you calculate time dilation in a gravitational field. I already know SR time dilation equations, t=t*sqr(1-v^2/c^2), I have even designed a software in VB to calculate it. But I do not know how to calculate time dilation in General Relativity. Can someone please tell me? Im trying to work GR into one of my theories. According to my software, if you travel at a speed of 55 MPH for 1 hour, you will have traveled 0.0119904086659517 nanoseconds into the future , hehe. And if it is at all off, blame google.