You got a binary file and wish to find closest match to it among thousands of binary present in a directory.

Using ssdeep:
Step 1: Create hash of file to be compared
$ ssdeep -b file2876.bin > hash.txt
$ cat hash.txt
768:E99YjTI9Z/PnxoKcnZtr6U4sf+BTDfBgfjeMJbQU6c2t0DP:ELQK4ZQUhf+W T576aP,"file2876.bin"

Step 2: Now compare this hash against all the files in directory
$ ssdeep -bm hash.txt /path_to_directory_having_files/*
file2313.bin matches hash.txt:case2876.bin (99)
...that's 99% match