The Houston Texans, with a record of 2-14, had the worst season in the 2013 NFL regular season.
The Cleveland Browns had the worst record in the 1999 NFL season with a record of 2-14. The New Orleans Saints had the second worse record, finishing the season at 3-13.
Detroit Lions 0-16
2008 Detroit Lions: 0-16
The Pittsburgh steelers, with a record of 1-13
The Saint Louis Rams had the worst record in the 2009-2010 season, they ended their season 1-15.
The 2008-2009 Detroit lions (0-16)
2008 Detroit Lions, 0-16
Through the 2010 season, the Carolina Panthers posted a 2-and-14 record.
In the NFL, that was 1-15 by the St. Louis Rams.