All MMA fights are 3, 5-minute rounds, with a minute break in between rounds. Championship fights, as well as main events in the UFC (even if it's not a championship fight) are 5, 5-minute rounds.
If a fight has not been stopped due to knockout, TKO, or submission, the judges scorecards will be read to determine the winner.
Three judges score each bout on a "10-point must system". Each round is scored individually with the winner of a round awarded a 10, and the loser of the round awarded 9 or less.
This is based on damage, effective (ie. landing clean, powerful) strikes, effective grappling, and if all the other criteria are equal, aggression and cage control.
A round that is scored completely even (a draw) would be scored 10-10 (very rare), a round with a winner is a 10-9, where a very dominant round is given a 10-8. Whoever has the most points at the end of the fight is declared the winner on that scorecard.
As scoring fights is subjective, judges are often criticized for their decisions, sometimes unfairly in the case of close fights, but often justifiably as judges regularly turn in largely indefensible scorecards - if you're new to watching the sport (or any combat sport), get ready to see some infuriating decisions.
The types of decisions are as follows:
Unanimous Decision: all three judges score the bout for the same fighter, who is declared the winner.
Split Decision: two judges score the bout for fighter A, one judge scores it for fighter B. Fighter A is then declared the winner. This is common with close fights, or with really bad judging.
Majority Decision: two judges score the bout for fighter A, while the third scores it a draw. Fighter A is declared the winner; this type of decision is quite rare.
Draw: draws are extremely rare in MMA, but do occasionally happen (and should happen more frequently, in the case of a very close fight). Like normal decisions, there can be a unanimous draw (all three judges score it evenly), a split draw (one judge calls it a draw, other two judges score it for opposite fighters), or a majority draw (two judges call it a draw, therefore the third scorecard is ignored).
In general, a stoppage occurs when A) a fighter is rendered unconscious, B) a fighter "taps out" or submits, or C) the ref determines a fighter is no longer intelligently defending themselves. Here are the different stoppage types and possibilities:
Knockout: this one is obvious; the ref stops the bout when a fighter is rendered unconscious from blows to the head. Sometimes fighters will actually be knocked out and wake up almost instantly (called a "flash" knockout, where you can see their eyes roll back and their body go limp for a moment) - if the ref spots this, they'll typically stop the fight, but often a fighter will recover so quickly the ref doesn't even have a chance to stop it or the fighter is already back into the fray and thus is allowed to fight on.
Unlike boxing, MMA includes ground fighting, and when a fighter is knocked down, the opposing fighter is free to get on top of them and continue striking them or look for a submission - there is no break in action or 10-count to see if they can continue.
Contrary to popular belief, this is actually a safer system. With the count method, fighters can be completely knocked out and still recover enough to stand up after 10 seconds, thus they can continue and proceed to take more punishment and be knocked out again, suffering multiple concussions in the same fight (which is extremely damaging).
Technical Knockout: a TKO can occur under various circumstances and is generally subjective and up to the referee.
Generally, these occur when a fighter is no longer able to defend themselves. Perhaps they were knocked down, are still conscious but dazed and simply covering up on the ground rather than fighting back while their opponent continues hitting them, or maybe they got hit with a body shot and are in such pain they curl up in the fetal position and no longer fight back. It can also happen if a fighter is unable to continue due to an injury or damage; for instance, if a fighter keeps receiving leg kicks and can no longer stand up to fight, a TKO will be called as the fighter can't continue.
Another case would be the instance of a broken bone or other injury, where either the ref sees the injury and calls the bout to protect them or the fighter signals they're injured and can't continue (a broken arm for instance). The ref can halt the bout at any time to call the ringside doctor in to check on a fighter and see if they're too injured to continue; typically this is done to check on cuts, or if a fighter's eye is extremely swollen to see if they can see.
In the case of a bad cut, generally, as long as there isn't a gaping wound, the fight will continue as cuts are just superficial; however if a cut is bleeding right into a fighter's eye(s) and thus causing them to be unable to see, or if it's in a really bad spot (like an eyelid which can damage the eye) the fight can be stopped. If a fighter's eye is swollen completely shut, the fight will also be stopped as they can no longer see shots coming from that side.
Submission: while KO/TKOs exist in boxing and kickboxing, submissions are unique to MMA and grappling martial arts. Essentially, a fighter will tap out (or verbally say they tap, usually in the case that their arms are trapped) if they are caught in a submission hold; these can range from hyperextending a fighter's knee in a leglock, torquing an opponent's arm to its breaking point in an armbar or kimura, or various forms of chokes which will render a fighter unconscious.
If a fighter doesn't tap out, depending on the submission they're in they risk having a bone broken, ligaments and tendons torn, continued intense pain (obviously), or losing consciousness. Of course, most fighters will tap when they know they are unable to get out of a submission.
You'll sometimes see fighters who refuse to tap when defending a choke, and the ref will stop the bout as soon as they see the fighter lose consciousness. This is actually completely safe: when under supervision, so long as the choke wasn't held way after the person is unconscious (which should never happen when a ref is there to stop it), it is quite easy to revive the person choked unconscious, and there are no ill long-term effects of being choked out - you simply forget the last few seconds prior to going unconscious, and may feel lightheaded for a few minutes (and depending on the choke, your neck may be a bit sore), but your brain suffers no damage or other affects.
Technical Submission: a "technical" submission means that the fighter did not tap out or "submit", rather the ref was forced to stop the fight due to a submission hold; either the fighter was choked unconscious or had their arm broken/dislocated and thus the ref stepped in to end the bout.
No Contest: a No Contest or NC typically occurs when a foul results in a fighter being unable to continue. This can be from something like a painful groin shot or a bad eye poke. In order for the bout to be ruled a No Contest in these cases, the foul must be ruled by the ref to be accidental. This is of course subjective and dependant on the referee.
A No Contest can also occur retroactively - say if a fighter was fouled right before being finished by a submission and the ref didn't see/call it, and that foul is deemed sufficient enough to have caused the submission, they can file an appeal to the athletic commission to investigate and overturn the result to a No Contest (it's rare a commission overrules a referee's call, but it has happened).
A No Contest can also occur if a winning fighter fails a drug test; fighters are tested on fight night (and in the UFC are tested randomly throughout the year by USADA) and as it takes several weeks to get results, often a failed drug test occurs after a bout has already taken place. In those cases, if a failed test occurs and is proven correct (ie. the fighter didn't have a sufficient excuse), then the fight is turned into a No Contest. If the losing fighter fails a drug test after the fight, the result is unchanged so long as the other fighter didn't fail as well, in which case it would turn into a No Contest as well. Essentially, a No Contest is a wash; it simply gets added as an NC on a fighter's record and doesn't mean much.
Disqualification: a disqualification (or DQ) of course occurs when a fighter is deemed to have intentionally fouled their opponent, either causing a stop to the bout or forcing the referee to stop the bout after repeated fouls.
A referee can take points away from a fighter (that's reflected on the judges' scorecards) if they repeatedly foul an opponent or cause significant damage to their opponent via a foul, however if the foul is deemed flagrant or intentional, the ref can disqualify a fighter outright. This results in the offender losing the contest and the fouled fighter is awarded a win. These are very rare especially at the higher levels of the sport.
These are the general rules and fouls in a sanctioned MMA fight. These rules are adopted by athletic commissions in North America and Europe and are used by the UFC, though some other organizations (like Rizin in Japan or ONE FC in Singapore) incorporate slightly different rules for their events.
Depending on the foul, a ref can halt the action to warn a fighter about a foul, can take a point (or multiple points) away from the offending fighter, can halt the bout and restart the fighters in a neutral position (for instance, if someone grabbed the cage to help them take down their opponent, the ref can stand them up so the offending fighter wasn't rewarded with a dominant position by cheating), or in extreme circumstances, disqualify a fighter should they perform an egregious/intentional foul or repeatedly foul their opponent.
Most of these rules are pretty self-explanatory and obvious, but there are some that may seem odd that have been given clarification:
No headbutts (an accidental headbutt results in the fighter(s) being given time to recover and checked by the attending doctor to determine if they can continue)
No gouging/poking of the eyes (this happens sometimes given the open-fingered gloves; a fighter gets time to recover and, if needed, the doctor can be called in to check on them should they be poked in the eye)
No hair pulling
No fish hooking (essentially putting a thumb or finger in an opponent's mouth, then pulling on their cheek like a fish hook - it's extremely painful and dirty)
No putting a finger into an orifice or cut (along with the above rule, essentially don't do weird shit and don't stick your finger into a cut try to rip it open, that's just gross)
No groin strikes. For low blows, a fighter is given up to 5 minutes to recover. The fighter can choose to continue before this time is up; if the full 5 minutes passes and the fighter or doctor determines they can't continue, the fight is ruled either a No Contest or DQ based on the ref's discretion
No small-joint manipulation (so no pulling back on an opponent's fingers or toes to break them)
No striking to the spine or back of the head. This is an important rule, as blows to the back of the head are disproportionately damaging and can kill someone while damage to the spine can of course cause paralysis. Hitting the back and kidneys is perfectly legal though, so long as the strikes aren't to the spine
No throat strikes of any kind (you unfortunately can't karate chop someone in the neck)
No scratching/clawing or pinching
No kicking, kneeing, or stomping on the head of a grounded opponent. A fighter is considered "grounded" if they have A) a knee on the ground B) both knees on the ground C) both hands on the ground or D) they are on their back/butt. You can still punch and elbow the head, and strike any other legal area with kicks and knees, just not the head
No grabbing/holding the cage or top of the fence (you can put you hand or body on it, you just can't actually grab it with your fingers/toes)
No grabbing/holding the shorts or gloves of an opponent
No elbowing straight down (throwing from 12 on a clock face down to 6). This rule is simply stupid and should be removed - basically the commission's and doctors back in the day were afraid of the damage caused by downward elbows after seeing demonstrations of people breaking bricks with elbow strikes going straight down. Instead of banning elbows outright, as a middleground referee Big John McCarthy convinced them to only ban downward elbows as those were deemed more powerful (because of the demonstrations), when in reality you can actually generate just as much force if not more throwing elbows from other angles
No attacking an opponent before the ref has signalled the start of the bout
No attacking an opponent after the referee has signalled a stop or break in action
No attacking an opponent after the bell rings to end the round
No throwing an opponent out of the cage/ring (Tank Abbott actually tried to do this but was stopped by the referee before it was made an official rule)
No using abusive language in the cage/ring (kind of a weird one as some fighters will talk shit during a fight and usually the referees don't care)
No spiking an opponent on their head/neck. Basically, you can't pick someone up and slam (spike) them directly on their head/neck, but otherwise slams are legal
No interference from a fighter's corner. A corner person is allowed in the cage in between rounds to give their fighter water, apply ice, wipe their sweat with a towel, give them advice, etc., but otherwise can't enter the cage during a bout nor can they throw anything into it
No applying any foreign substance to the hair/body to gain an advantage. This is called greasing and is typically used to make someone more slippery and therefore avoid being grappled or help them get out of submission attempts. Vaseline is allowed only on a fighter's face
No timidity. This includes running away from the opponent without attacking, purposely letting your mouthpiece fall out repeatedly to cause a pause in action, or faking an injury/foul (this is all based on the referee's judgement)
The UFC holds their bouts in an eight-sided caged enclosure, dubbed the Octagon (which is patented, so other promotions usually use a circular or hexagonal cage, or a boxing ring).
While it was initially meant as a way to increase the spectacle of fighting, it's proven to be a safer, more practical fighting area than other enclosures such as a boxing ring. With the cage, there's leeway when a fighter falls or gets pushed into it, there's no chance (so long as the cage door is properly locked) of a fighter falling out of it (which happens in boxing, and can cause bad injuries since the ring is elevated so people can see it better), and it's better for the action as nobody can get tangled up in ropes.
The cage walls are actually used a lot by fighters both offensively and defensively. Similar to how boxers will force their opponents into the corners of the ring so they can't escape their punches, pinning an opponent against the cage can provide a fighter with good positions to land solid shots from, can stop them from moving backward to escape a strike, and can help pin the fighter when grappling to prevent them from being able to scramble up to their feet.
Fighters have learned how to use the cage to help stop themselves from being taken down or to aid them in returning to their feet by "wall-walking". One fighter, Anthony Pettis, has on multiple occasions even jumped off of the cage walls to throw unique strikes, including his famous Showtime kick.
Contrary to popular belief, boxing gloves were never made to protect a fighter's head - they were meant solely to protect a fighter's hands. Your hands consist of tons of small bones and are actually quite brittle; if you throw a punch with decent force and connect on say a forehead (one of the hardest spots on the human body), an elbow, or even a shoulder, there's a good chance you'll break your hand.
Thus boxing gloves were made - while they protect one's hands, they actually cause more harm to a person's brain. Despite the padding, having the hand so well protected allows someone to throw with much more power and adds weight to the blow. Though a padded punch is less likely to open a cut, the impact on the recipient's body is notably harder. It's simple physics really - force is mass x acceleration; gloves add more mass, the protection means you can throw harder shots without breaking a hand thus more acceleration. The combined result is a lot more force is hitting your skull.
Unlike in boxing, because grappling requires the use of your hands (good luck trying to lock up an armbar while wearing boxing gloves), MMA fighters wear small, 4-ounce gloves. These gloves (and the tape applied to the hands and wrists underneath) do little more than provide some protection for the knuckles and wrist, while still allowing the use of someone's hands for grappling.
The difference in gloves is actually a large factor in striking - boxers not only have more protection for their hands, but they can also defend themselves easier simply by hiding behind their gloves and using them to block incoming shots, where in MMA there's little more than your own hands to protect you from incoming shots. It's also easier to see punches coming when using boxing gloves since the gloves are much larger.
This is kind of obvious - all fighters wear shorts in the cage. They can have different styles (some like them loose and baggy, others like them super tight like spandex almost) and fighters wear a cup to lessen the pain if they accidentally get hit in the nuts (it happens, especially since one of the most effective weapons in fighting is the leg kick). Women of course wear shorts as well, and have a few options to cover their upper body like a tight fitting shirt or a sports-bra type top. Shoes were allowed back in the early days of the sport (as well as gis, the loose martial arts outfits most people know from karate) but of course are no longer allowed.
Something no fighter ever wants to forget, every fighter has to have a mouthguard to (try to) avoid getting their teeth knocked out.
All promotions (at least in countries where there's government regulation) have to hire certified cut men (or women) who attend to fighter's cuts and swelling in between rounds (same as in boxing), with one working on each corner during every bout.
Before a bout and between rounds, a cutman applies vaseline to a fighter's face - if a punch doesn't land clean, the hope is that the opponent's strike will simply slide off and not open a cut. It does work decently well, but cuts are still very common, especially in MMA where elbows and knees are perfectly legal, thus not just a padded glove is contacting the face.
Between rounds, cutmen try and seal cuts with vaseline and reduce any swelling with ice while a fighter's corner gives the athlete advice.
Like other combat sports, there are weight classes in place to make fights more fair. Like in boxing or wrestling, fighters tend to cut weight to make their weight limit - usually this is done by cutting water weight in the last few days prior to weigh ins, essentially dehydrating themselves in order to shed weight quickly and come in under the weight limit.
Weigh-ins take place the day before the fight, so fighters have plenty of time to rehydrate and eat to get back to their normal weights; some fighters will cut drastic amounts of weight in order to be "big" for their weight class, which can give them an advantage, but this is also very rough on their bodies and can make them sick or negatively impact their performance.
Often, cutting 5-10% of their body weight is normal for a fighter. If a fighter misses weight, their opponent has the choice to refuse to fight them and still earn their show money; if they choose to face them anyway, the fighter who missed weight forfeits a percentage of their purse to the fighter who made weight as punishment, typically 20%, though fighters will often negotiate for more depending on how much the fighter missed weight by and other circumstances.
Typically, like in boxing, the lower weight classes feature quicker and more technical athletes, where the larger weight classes feature more strength and power, but less technique and cardio due to their size.
Here is a list of the weight classes in the UFC (used for all of MMA in North America):
Women's Strawweight: 106-115 pounds
Women's Flyweight: 125
Women's Bantamweight: 135
Women's Featherweight: 145
Flyweight: 116-125 pounds
Light Heavyweight: 205
Note: the weights above are the targeted weight. A fighter must weigh this amount or lower, and MORE than the lower weight class. So for instance, a Lightweight must weigh 155 pounds or under, but needs to be at least 146 (over the lower weight class). Fighters are given a one pound allowance for weigh ins - for instance, if it's a lightweight bout, they can weigh 156 pounds. However, for a championship bout, a fighter must be exactly in the weight class and are not given this point allowance; for instance, at 155, if a fighter weighed in at 155.5 for a lightweight title fight, they missed weight and wouldn't be eligible to win the championship.
Commissions & USADA
Although in the early days of MMA promoters created their own rules and officiated their own events, in the early 2000’s the US government became involved to regulate mixed martial arts much like they do in boxing and kickboxing.
State Athletic Commissions (note it’s done at the state level, there is no national officiating body) were implemented many years ago in boxing to prevent fighter deaths (which was a problem in boxing at one time and still sometimes occurs in other countries, mostly from pre-existing conditions that aren’t checked for before they fight, but has never happened in a major MMA promotion). Cheating was also a major issue in boxing since the dawn of the sport, with fighters using loaded gloves (ie. adding weight or hardening material), boxers being paid to throw matches or “dive”, and clearly biased refs and judges officiating in favour of whoever paid them.
The commission system was necessary and provided many benefits. The commission for an event taking place in their state (or province/country in the case of Canada, Brazil, the UK, etc.) provides the officials (judges, refs) and ensures promoters adhere to a set of rules all promoters must follow, including having every fighter complete full medicals and brain scans prior to a bout. They of course also ensure fighters and their coaches/staff adhere to the official rules and have the authority to discipline those that break the rules.
In exchange for their services, the commission receives a small portion of the revenue generated from an event. Due to it being run at a state-level, the efficacy of the commission system greatly varies - some commissions do a great job (California for the last few years has been great for example, and continue trying to find new ways to help fighters and promote safety) while others are known for being incredibly inept (New York, Texas, Pennsylvania) and even corrupt (New York, Nevada).
The athletic commissions are also responsible for drug testing athletes to check for steroids and other performance enhancing drugs (PEDs) for each bout. This started being done many years ago on the night of a fight, at first just for larger events and the main fights (as it was expensive) but soon this program expanded to cover most events of a decent size, including everybody on a major promotion's card.
These tests were known to be essentially IQ tests - if you know anything about PED’s, most of them are much more effective if taken and cycled off of well before the competition date, and if you know the date that you’re going to be tested, it’s very easy to clear most PED's out of your system in order to pass a drug test.
After steroid use continued to be talked about as rampant in the sport (which was not just an MMA problem, but a sporting problem, and the reality is the majority of pro athletes in major leagues or competitions such as the Olympics, the NFL, the MLB, etc. are taking or have taken PEDs) some commissions like California started doing random drug tests weeks and even months before big fights. These tests were not only better for being random, but they were also more comprehensive (and expensive), testing fighter's blood rather than just urine.
After several high-profile failed tests in the expensive program that was only being applied to higher-profile fighters due to the costs involved, the UFC enlisted the help of USADA (the US Anti-Doping Agency) to test their entire roster year-round. They implemented a program similar to the Olympics (though because of the much smaller roster size, much more focused testing is possible) starting on July 1 2015.
Since then many high-profile fighters have failed tests, including Anderson Silva (who also failed prior to USADA being implemented, when commissions had first started testing prior to fight night), who was regarded as the best fighter in MMA history for a time, and Jon Jones, a sublime talent who also has a knack for constantly getting caught cheating.
This implementation of USADA PED testing has had many drawbacks however; first and foremost, it is incredibly taxing on the fighters, who have to constantly provide their whereabouts to USADA and worry about every supplement or medication they take, as many substances on the banned list can be found over the counter at any pharmacy or nutritional store.
There are still many ways to beat the tests (drug testing and doping in sports could easily comprise a whole separate guide in itself) and many of the fighters who have been flagged from USADA have legitimately not been trying to cheat. Many fighters have proven to have taken supplements that did not list any banned substance on the label, but actually contained banned substances in them (the supplement market is really bad for cross-contamination and spiking products). Overall, USADA has done as much harm as good for the UFC, and has sullied the name of many fighters over positive test results despite later proving their innocence, not to mention many big fights having to be cancelled sometimes just days before the fight was to take place.
Doping is a tough issue in sports and while the UFC is doing more than most sports in that regard, it's still an inconvenient reality that many if not most professional athletes cheat and the protocols that are put in place to catch them punish just as many if not more innocent people as cheaters.