Total QBR is a quarterback rating that takes into account all of a quarterback's contributions (passing, rushing, sacks, fumbles, penalties) to his team's scoring and winning and summarizes them into one number on a 0-100 scale, on which 50 is average.
For a season, a Total QBR of 65 or better is roughly Pro Bowl level and a rating of 75+ is MVP level. For more about the methodology and statistics behind Total QBR, see here.
With his spectacular Week 4 performance, Aaron Rodgers moves barely ahead of Tom Brady for the overall lead in Total QBR this season. Matt Hasselbeck's great game vaults him into third place on the year, while Ryan Fitzpatrick's rough performance drops him from second all the way down to fifth. Jaguars rookie Blaine Gabbert brings up the rear with a Total QBR of 12.1 through Week 4.
Below is the full breakdown of Total QBR and its component statistics for the 32 NFL QBs on pace for 250 action plays this season.