A taekwondo contest involves two athletes, "Chung" (blue) and "Hong" (red), trying to earn points by landing kicks to the opponent's head and body, or punches to the body. A contestant can win by knocking out the opponent (which is rare at the elite level), by scoring the most points, by default (if the opponent earns five penalty points), or by disqualification of the opponent. When there is a 12-point difference between the two athletes at the time of the completion of the second round, and/or at any time during the third round, the referee shall stop the contest and shall declare the winner by point gap.
A contest consists of three rounds, with each round lasting two minutes. There is a one-minute rest period between each round.
At the start of a contest, the competitors stand at attention and bow to each other, on the referee's Korean commands of "cha-ryeot" (attention) and "kyeong-rye" (bow) respectively. The referee then calls out "joon-bi" (ready) and the "shi-jak" (start) to begin the match.
Points are earned for each legitimate strike delivered to a scoring area on the opponent. The two legal scoring areas are the body (the blue or red area of the trunk protector) and the head (the area above the collar bone, including the neck, both ears and the back of the head). Hits below the waist are forbidden. The blows must be delivered accurately and powerfully to those scoring areas.
Also, strikes can only be delivered using the permitted parts of the body. A punch to the body must be delivered with the front of a firmly clenched fist, and a kick with part of the foot below the ankle.
Points are awarded as follows:
- One point for an attack on the trunk protector (punch or kick)
- Three points for a turning kick to the trunk protector
- Three points for a kick to the head
- Four points for a turning kick to the head
- One point for every two warning penalties, or every deduction penalty given to the opponent
The measurement of whether or not a strike is delivered powerfully is made electronically by the electronic Protector and Scoring System (PSS). The force of impact threshold varies by weight class and gender.
Valid points for strikes will be recorded automatically by the PSS system. In the case of turning kicks to the trunk protector or head, the "valid point(s)" shall be scored automatically by the PSS system, while the "valid turn" must be recognized and registered by at least two of the three judges.
Taekwondo has two types of penalties - kyong-go and gam-jeom - which are counted in the total score of the three rounds.
The most common, a kyong-go, or warning, equals a half-point penalty. It is counted only when two are added together. At that point, the two kyong-go are counted as an addition of one point for the opposing contestant. The odd kyong-go shall not be counted in the grand total. A kyong-go is assessed for such offenses as:
- crossing the boundary line
- falling down
- avoiding or delaying the match
- hitting the opponent's head with the hand
- uttering undesirable remarks
- any misconduct on the part of the contestant or coach.
A gam-jeom, or more serious penalty, means the awarding of one point to the offender's opposition. Typical offenses include:
- throwing down the opponent
- attacking the opponent after a "kal-yeo" (break)
- attacking the fallen opponent
- intentionally attacking below the waist
- interrupting the progress of the match
- violent or extreme remarks by the contestant or coach
- deliberately attacking the opponent's head with the hands.
When a contestant is assessed five penalty points (regardless of classification as to kyong-go or gam-jeom), the referee shall declare him/her the loser by penalties.
When a contestant is knocked down, the referee begins a 10-second count, as in boxing. In taekwondo, a person is knocked down if any part of the body other than the sole of the foot touches the floor as a result of an opponent's applied force. The referee can also declare a knockdown if a contestant is staggered and shows no intention or ability to continue, or the referee judges that the contestant cannot continue as the result of being struck by a legitimate technique.
Once a knockdown has occurred, the referee calls out, "kal-yeo," meaning "break." This tells the other contestant to back away while the referee begins counting from 1 ("ha-nah") to 10 ("yeol") in Korean in one-second intervals. Even if the downed contestant stands up and wants to resume, he or she must wait while the referee continues counting to 8 ("yeo-dul"). The referee then determines whether the contestant is fit to continue. If not, the other contestant wins by knockout. If the contestant is deemed fit to continue, the referee resumes the contest by declaring "kye-sok" (continue).
After coming under criticism for its scoring procedures at the Beijing Games, the World Taekwondo Federation implemented a video replay system in time for the London Olympics in 2012.
A coach will be allowed one appeal per athlete from the preliminary round until the medal contests. The appeal quota is reset when an athlete advances to a medal contest so that each athlete's coach has one appeal for the medal contest.
If an appeal is successful and the contested point is corrected, a coach retains his appeal right.
Appeals are made by a coach to the center referee by raising a blue or red card, corresponding to the color of the athlete's trunk protector. The center referee then requests the Review Jury to review the video replay. The Review Jury must inform the center referee of the final decision within one minute of the appeal being reported to the Review Jury.
Appeals for video replay are limited to only one action that has occurred within five seconds from the time of the coach's request. Appeals for video replay are limited to the following:
- errors of the center referee in application of competition rules
- points awarded by the judges
Golden point round
If any contest ends in a tie, the participants go into a fourth "golden point round" - a sudden-death round that last two minutes - after a minute of rest following the third round. When a contestant scores the first point in the sudden-death round, that contestant is declared the winner. When a contestant receives a gam-jeom in the sudden death round, their opponent is declared the winner. If nobody scores in the round, the refereeing officials decide the winner by deeming who was superior in the sudden-death round using the following four criteria:
- Technical dominance of an opponent through aggressive match management
- A greater number of techniques executed
- The use of more advanced techniques, both in difficulty and complexity
- Display of a better competition manner