TO BREAK A TIE WITHIN A DIVISION
If, at the end of the regular season, two or more clubs in the same division finish with identical won-lost-tied percentages, the following steps will be taken until a champion is determined.
Two Clubs
Head-to-head (best won-lost-tied percentage in games between the clubs).
Best won-lost-tied percentage in games played within the division.
Best won-lost-tied percentage in common games.
Best won-lost-tied percentage in games played within the conference.
Strength of victory.
Strength of schedule.
Best combined ranking among conference teams in points scored and points allowed.
Best combined ranking among all teams in points scored and points allowed.
Best net points in common games.
Best net points in all games.
Best net touchdowns in all games.
Coin toss
Three or More Clubs
(Note: If two clubs remain tied after third or other clubs are eliminated during any step, tie breaker reverts to step 1 of the two-club format).
Head-to-head (best won-lost-tied percentage in games among the clubs).
Best won-lost-tied percentage in games played within the division.
Best won-lost-tied percentage in common games.
Best won-lost-tied percentage in games played within the conference.
Strength of victory.
Strength of schedule.
Best combined ranking among conference teams in points scored and points allowed.
Best combined ranking among all teams in points scored and points allowed.
Best net points in common games.
Best net points in all games.
Best net touchdowns in all games.
Coin toss
SOURCE:
http://www.nfl.com/standings/tiebreakingprocedures