1760, 55 Players on a roster, 32 teams, 55 x 32 = 1760. However, there can be an unlimited amount of free agents so the number of players in the NFL can constantly change.
53 for NFL and 15 for NBA
30 as of the 2008 season
Playing now... 33 http://espn.go.com/nfl/college/_/letter/n
Some 1,800.
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