Regulation time for all men's matches will be five minutes, and regulation time for all women's matches will be four minutes. There are not multiple rounds during regulation time, but if there is no winner at the end of regulation time, judokas will compete in a sudden-death "golden point" overtime.
At the end of a match, the competitors will adjust their judogi and face one another. Once the referee indicates the winner, the two competitors will bow to each other before leaving the mat.
There are three different types of scores in judo, listed below in order from highest-scoring to lowest-scoring.
1. Ippon: A full throw in which a contestant throws his opponent to the mat with "considerable force and speed" so the opponent lands "largely on his back." An ippon is also awarded when a contestant immobilizes his opponent with a grappling hold-down for 20 seconds, or when an opponent gives up or passes out. An ippon immediately ends the match. Equivalent to a knockout in boxing or a pin in wrestling. Referee's hand signal: arm straight up.
2. Waza-ari: A throw which shows power and superiority but isn't clear enough to be an ippon, either because the opponent didn't land "largely on his back" or because the throw lacked speed or force. Waza-ari is also awarded for immobilizing an opponent for 15 seconds or more, but less than 20 seconds. Earning two waza-aris in a match is equivalent to an ippon and will immediately end the match. Referee's hand signal: arm out at shoulder level from the side.
3. Yuko: Usual definition is "almost waza-ari." A yuko is awarded for a throw that is "partially lacking" in two of the three elements of an ippon: putting the opponent on his back, speed of throw, force of throw. A common yuko is throwing an opponent on his side, as opposed to on his back. A yuko is also given for immobilizing an opponent with a hold for 10 seconds or more, but less than 15 seconds. No number of yukos equal a waza-ari or an ippon in the final tabulation of the match's outcome. Referee's hand signal: arm 45-degrees out from the side.
When watching a judo match, there will typically be a scoreboard that reflects the various scores that the competitors have earned during the match. The scoring is actually displayed as three separate columns, with a tally shown for each of the different types of scores. However, to better understand the scoring, it may be easiest to look at the scoreboard as if it were showing cumulative point totals. Below are the "point equivalents" that would correspond with each type of score.
- Ippon = 100 points
- Waza-ari = 10 points
- Yuko = 1 point
There are two levels of penalties in judo, listed below from most severe to least severe.
1. Hansoku-make: Grave infringement. Calls for immediate disqualification of the offending judoka. Can be assessed for fouls such as intentionally trying to injure the opponent, unsportsmanlike conduct or for repeated violations of the rules. The negative equivalent of an ippon.
2. Shido: Slight infringement. Assessed for any rules violation that does not merit immediate disqualification. Some examples are: non-combativity (player does not attack enough), intentionally stepping out of bounds, playing too defensively, putting a hand directly on the opponent's face. The first three shidos are warnings. If a competitor receives a fourth shido in one match, those shidos become a hansoku-make, which immediately ends the match.
Ways to win
The following are ways a match could end before time expires.
- Scoring an ippon (the four ways to end a match by ippon are described in the next section)
- Scoring two waza-aris
- Opponent receives a hansoku-make penalty for a serious rule violation
- Opponent receives four shido penalties for minor rule violations
- Opponent withdraws due to injury
If the match goes the distance, the winner is decided on the basis of which judoka has accumulated the highest quality score. Whichever judoka has more waza-aris will win. If the number of waza-aris is the same, then whichever judoka has more yukos will win. (In judo, it is always the highest quality score that wins, so one waza-ari will beat any number of yukos.) If the point totals are the same, the outcome is decided in favor of whichever judoka has accumulated fewer shidos (penalties).
If the point totals and number of penalties are the same, then a winner is decided by "golden score," which is essentially sudden-death overtime. The clocks are reset, and the first person to score is the winner. A player can also win if the opponent is given a shido during the golden score period. There is no time limit.
Ending a match by ippon
The following are the four ways that a judoka can score an ippon.
1. Throwing an opponent to his back with force, speed and control. This would be considered a "perfect throw" in judo.
2. Immobilizing an opponent with a hold-down (grappling) technique for 20 seconds. The opponent must be mostly on his back (not necessarily with the shoulders touching) and no part of the holder must be under the control of the person being held (i.e. no entangled legs). When the hold-down is started, the referee announces "osaekomi" and the clock is started to time the duration of the hold.
3. Choking an opponent until he "taps" (gives up) or "naps" (passes out). Pressure is applied to the sides of the neck, windpipe or larynx. A properly applied choking technique can cause the opponent to pass out.
4. Applying an armlock to an opponent's elbow joint until he gives up or the arm becomes dislocated.
A competitor can give up by "tapping out." During a tapout, the surrendering judoka taps their arm, mat, self, or opponent repeatedly to ask him to release the technique. The surrendering judoka can also say "maitta" (I give up). Tapouts most commonly occur when a judoka is being choked and in danger of passing out, or when a judoka is in an armbar and in danger of having their elbow dislocated.
Once a judoka taps out, the match is over, and their opponent wins by ippon.