Below you can see the front view size comparison of Nikon D750 and Nikon D7500. Nikon D7500 is clearly the smaller of the two cameras. Its body is 5mm narrower, 9mm shorter and 5mm thinner than Nikon D750.
Nikon D750 vs Nikon D7500 - Front View
Nikon D750 vs Nikon D7500 - Top View
The chart below depicts how two cameras compare with average dimensions of the cameras in their class.
Camera Size Comparison
Select Two Cameras for Size Comparison