Bib number

In many sports, a competition number is used to identify and differentiate the competitors taking part in the competitive endeavour. For example, runners in a race may wear a prominent competition number so that they may be clearly identified from a distance. It is also called a bib number when worn on a bib over, or affixed to, the athlete's top.

In motorsport, competition numbers are attached to the vehicles taking part, also for identification. In some types of motorsport such as rallyes, the competition number works in conjunction with special kinds of timing system (for example targa timing) and as a result numbers also usually relate to the competitors' due time and thus may exhibit gaps such as skipping from number 59 to number 100 (59 minutes to 1 hour due time).

Since the 2000s, track and field athletes at major competitions wear their names as well as their numbers on their bibs. In relay events, all team members have the IOC country code. Track athletes also wear a lane number on the shorts.

1980 Olympic 5000m Competition numbers on bibs

2009 World marathon Surname on front of bib

2009 World steeplechase Number on back of bib

2009 World 4 × 400 m relay JAM for the Jamaican team

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