A biathlon competition consists of a race in which contestants ski around a cross-country track, and where the total distance is broken up by either two or four shooting rounds, half in prone position, the other half standing. Depending on the shooting performance, extra distance or time is added to the contestant's total running distance/time. As in most races, the contestant with the shortest total time wins.

For each shooting round, the biathlete must hit five targets; each missed target must be "atoned for" in one of three ways, depending on the competition format:

• by making a skiing round in a penalty loop
• by having one minute added to one's total skiing time, or
• by having to use an "extra cartridge" (placed at the shooting range)
  to finish off the target

Skiing Details
All cross-country skiing techniques are permitted in biathlon, which means that the free technique is usually the preferred one, being the fastest. No other equipment than skis and ski poles may be used for moving along the track. Minimal ski length is 4 cm less than the height of the skier.

Shooting Details
The biathlete carries the 3.5 kg small bore rifle including ammunition in magazines on her/his back during the race. The rifles use .22 LR ammunition and are bolt action.
The target range shooting distance is 50 m or 164 feet. There are five circular targets to be hit in each shooting round. When shooting in the prone position the target diameter is 45 mm or 1.7 inches, when shooting in the standing position the target diameter is 115 mm or 4.5 inches. On all modern biathlon ranges, the targets are self-indicating, in that they flip from black to white when hit, giving the biathlete as well as the spectators instant visual feedback for each shot fired.

Individual
The 20 km Individual race (15 km for women) is the oldest biathlon event. The biathlete shoots four times at any shooting lane, in the order of prone, standing, prone, standing, totalling 20 targets. For each missed target a fixed penalty time, usually one minute, is added to the skiing time of the biathlete. Competitors' starts are staggered, normally by 30 seconds.

Sprint
The sprint is 10 km for men and 7.5 km for women. The biathlete shoots twice at any shooting lane, once prone and once standing, for a total of 10 shots. For each miss, a penalty loop of 150 m must be skied before the race can be continued. As in the Individual competition, the biathletes start in intervals.

Pursuit
In a Pursuit, biathletes' starts are separated by their time differences from a previous race, most commonly a Sprint. The contestant crossing the finish line first is the winner. The distance is 12.5 km for men and 10 km for women, there are four shooting bouts (two prone, two standing, in that order), and each miss means a penalty loop of 150 m. To prevent awkward and/or dangerous crowding of the skiing loops, and overcapacity at the shooting range, World Cup Pursuits are held with only the 60 top ranking biathletes after the preceding race. The biathletes shoot at the lane corresponding to the position they arrived. For example, arrive at the range in 5th place, you shoot in lane five, for all shooting bouts.