Below you can see the front view size comparison of Nikon D5300 and Nikon D5500. Nikon D5500 is clearly the smaller of the two cameras. Its body is 1mm narrower, 1mm shorter and 6mm thinner than Nikon D5300.
Nikon D5300 vs Nikon D5500 - Front View
Nikon D5300 vs Nikon D5500 - Top View
The chart below depicts how two cameras compare with average dimensions of the cameras in their class.
Camera Size Comparison
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