The current formula has each team play 16 regular season games for 2018-2019 following this rotation program:
2 games against each of your other three divisional rivals, 1 home game, 1 away game, totaling 6 games.
Your team will play another division within your conference (NFC or AFC) on a 3 year rotating cycle totally another 4 games.
Each team in a given division will face all teams in each of the other conferences 4 divisions on a 4 year cycle totalling 4 games.
Strength of schedule games: The remaining two games will be scheduled based on the record of a given team the prior season. This part of the schedule also factors in marque intraconference and divison matchups and prime time games like Thanksgiving, Hall of Fame Game, Thursday, Sunday & Monday Nights. As a general rule, these games put a 1st place team against the 2 first place teams in other divisions within their conference that were not part of the interdivision 3 year cycle. The 2nd, 3rd & 4th place teams are scheduled using this same relative rotation formula.