Situation is considered when grading QBs. PFF's algorithm will never fully be disclosed due to proprietary information (obviously), this is likely the most in-depth we can expect to be made available.

THE GRADING SCALE

Each player is given a grade of -2 to +2 in 0.5 increments on a given play with 0 generally being the average or “expected” grade. There are a few exceptions as each position group has different rules, but those are the basics. The zero grade is important as most plays feature many players doing their job at a reasonable, or expected, level, so not every player on every play needs to earn a positive or a negative.

At one end of the scale you have a catastrophic game-ending interception or pick-six from a quarterback, and at the other a perfect deep bomb into a tight window in a critical game situation.

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Each position has its own grading rubric so our analysts know how to put a grade on the various expectations for a quarterback on a 10-yard pass beyond the sticks or what the range of grades might look like for a frontside offensive tackle down blocking on a “power” play.

There is then an adjustment made to the “raw” grades to adjust for what the player is “expected” to earn given his situation on the field. For instance, a player’s grade may be adjusted down slightly if he plays in a situation that is historically more favorable while a player in more unfavorable circumstances may get an adjustment the other way. We collect over 200 fields of data on each play, and that data helps to determine what the baseline, or expectation, is for each player on every play.

Each grade goes into a specific “facet” of play in order to properly assess each player’s skillset. The facets include passing, rushing, receiving, pass blocking, run blocking, pass-rushing, run defense and coverage. Special teamers also have their own facets of kicking, punting, returning and general special teams play. Facets are important in order to have a clear view of where a player’s strengths and weaknesses lie.

A collection of grading examples across all facets of play is included on this page.