Far and away, the most successful submissions in Mixed Martial Arts are as follows:
#1: Rear Naked Choke (392 finishes)
#2: Guillotine Choke (188 finishes)
#3: Arm Bar (155 finishes)
#4: Triangle Choke (68 finishes)
#5: Arm Triangle, also known as the Head and Arm Choke (63 finishes)
The Kimura armlock is next in line, and with it the numbers begin to drop off steeply for successful finishes in Mixed Martial Arts, with only 35 kimuras counted in over 5,000 fights!
But for those who are curious, the D'arce choke and anaconda choke are next in line after the Kimura (both of which are covered in the Ultimate Chokes Escapes course).
In any case, the data is very clear.
Chokes, especially the Rear Naked Choke and the Guillotine, are the most successful submissions in Mixed Martial Arts.
Which, even with rules, is as close as martial artists have right now to a fight science lab where we can test what's effective.
Here are two graphs from the same website that put it very plainly: