If you are looking for a quick answer to, "Who has the most number of knockouts in boxing history?" — it is Billy Bird, with 139 KOs out of 356 fights.
As quick as this answer is, it is an equally boring answer. And probably it is not what you are really looking for. Maybe you actually want to know more, like, "Who are the top 10 or maybe the top 50 boxers with the most number of knockouts? Does my favorite boxer make it to the list? Does the boxer I don't like so much make it?", etc.
The answer to what you are looking for is actually not as simple as you would think. Someone could have fought 1,000 "tomato cans", and knocked all of them out. Is that what you are looking for? How meaningful is such a performance to you? Probably worthless and of zero interest.
So we have created two lists for you. One is about knockouts count in general, and the other is for knockouts in title fights. It is very likely that you will find the answer(s) to your question(s) in these two lists.
This list is about the most number of knockouts, irrespective of the quality of opponents or the relevance of the fights — purely numbers, with no significance of any kind.
Considering how infrequently the present day boxers fight, it is very unlikely that any of them will ever make it to this list. In fact, their fight record itself may never reach the least number of knockouts on this list. So this list is likely to be historical and is already set in stone.
Table of 50 boxers with the all-time highest number of knockouts.
|8||Sugar Ray Robinson||200||109||54.5|
|17||Julio César Chávez||115||86||74.8|
|18||Yori Boy Campas||128||83||64.8|
|19||Jose Luis Ramirez||111||82||73.9|
|38||José Luis Castillo||80||57||71.3|
|47||Marvelous Marvin Hagler||67||52||77.6|
|49||Marco Antonio Rubio||68||51||75|
The next list is a more meaningful one, since it is about knockouts in title fights instead of mere numbers. Of course, title fights don't always equal great matchups but there is better control in terms of opponent quality; and in the majority of cases, we get to see worthy opponents against the champions.
It is likely that you will look for a certain dominant champion with a very high knockout percentage on this list and will not find him or her. Why is that? That's because this list is not about knockout percentage. In fact, a list based on knockout percentage would be pretty meaningless — 1 KO out of 1 fight is 100%, just as 100 KOs out of 100 fights is — and the two are incomparable.
Table of 50 boxing world champions with the all-time highest number of knockouts.
|2||Julio César Chávez||37||21||56.8|
|10||Oscar De La Hoya||29||17||58.6|
|11||Ratanapol Sor Vorapin||24||17||70.8|
|16||Marco Antonio Barrera||30||15||50|
|19||Roy Jones Jr.||27||14||51.9|
|30||Marvelous Marvin Hagler||15||12||80|
|47||Floyd Mayweather Jr.||26||10||38.5|
Golovkin just needs three more knockouts to reach Joe Louis' record. Him being 40 years old may make it a difficult task, but if he can reach or surpass Louis' record, it would be quite an achievement.
Inoue is still young at 29, but he will have to knock out six more opponents to reach Louis' record. Considering he is moving up a weight class, knockouts may become harder to come by (we shall see), and if he reaches or surpass Louis' record, it would be an incredible achievement for someone who started fighting at light-flyweight (49 kg / 108 lb).
Billy Bird (139), Archie Moore (132), and Young Stribling (129) are the top three boxers with the higest knockout count. Joe Louis (23), Julio César Chávez (21), and Dariusz Michalczewski & Gennady Golovkin (20) have the three highest knockout count in title fights.
Hope this article provided you with the answer to the question you were looking for, and hopefully answered some more.