Predicting SHBG?

Total testosterone: 251 ref range: 241-827
Free testosterone: 4.7 ref range: 8.7-25.1
Is there a way to predict or come close to knowing what SHBG is from these two numbers?
I am going to a GP who didn’t test SHBG before starting trt. I’m having it tested in 2 weeks which will be 6 weeks into therapy so I’ll know then. I’d like input on if it’s possible to come close to knowing the value of SHBG if you know free and total testosterone. Thanks

Yes, if you have two you can figure the third. I bet a google for “shbg calculator” will get you to the right place.