Fujifilm X-T1 is a mirrorless camera and Nikon D7100 is a Pro DSLR, both features excellent core specification .. take a look at the major difference below
Nikon D7100 have more resolution compared to Fujifilm X-T1 but, the X-T1 offers more ISO range hence you get better low light images with X-T1 compared to Nikon D7100.
PDAF sensor in Fujifilm X-T1: The Fujifilm X-T1 comes with phase AF pixels within the sensor, the X-T1 quickly acquire focus during still, video or live view shooting, on the other hand the Phase AF of Nikon D7100 is active when you are using optical viewfinder otherwise during live-view mode and video mode only contrast AF is active.
Fujifilm X-T1 offers fast continuous shooting speed compared to Nikon D7100, but Nikon D7100 offers better shutter range ( 1/4000 vs 1/8000).
Fujifilm X-T1 offers tilting screen and you get a better option to compose your image compared to Nikon D7100.
Nikon D7100 offers optical viewfinder and better battery life compared to Fujifilm X-T1.
Built-In Wi-Fi Connectivity: Fujifilm X-T1 features built in WiFi connectivity on the other hand Nikon D7100 require WU-1a Wireless Mobile Adapter to enable WiFi connectivity.
Verdict: Fujifilm X-T1 offers better sensor and fast continuous shooting speed and on the other hand Nikon D7100 have more resolution + huge range of DX and FX lenses and Built-in i-TTL Flash and Speedlight Compatibility.
Finally, We recommend you to buy Fujifilm X-T1 based on specification comparison review.
I believed in Nikon until a pro friend of mine had a problem with marks on the sensor on his D600. Nikon’s handling of that problem was downright disgusting. It had been back 3 times!!!
From now on it is Fuji!
I now have a Fuji X-Pro1 kit and feel safe.