15 every time.
During the 1999 regular season, the Steelers offense was penalized a total of 945 yards. The defense was penalized a total of 813 yards.
fifteen
5 Yards
10
The offending team is sent back 10 yards.
For a delay of game, the team is penalized 5 yards.
15
In the NFL, the penalty is 15 yards. In college, the penalty is 10 yards.
There have been many teams that have gone an entire game without getting penalized. For a season, the record for fewest penalties in 19 held by the 1937 Detroit Lions. The 1937 Lions also holds the NFL record for fewest penalty yards in a season with 139.
15 yards and an automatic first down.
The penalty is 15 yards if the referees think the face mask was grabbed intentionally and 5 yards if they think it was incidental.