How to Calculate Passer Rating for an NFL Quarterback

Quarterbacks have a number of statistics that can represent how well they are performing, such as completion percentage, yards per attempt, touchdown passes and interceptions. However, all of the statistics represent different aspects of the game. In an attempt to represent a quarterback's performance with a single number, the NFL calculates a quarterback passer rating that takes into account all these statistics. The passer rating can be calculated for any period of time, such as a single game, a season or a career.

Instructions

    • 1

      Divide the number of pass completions by the number of pass attempts to find the quarterback's completion percentage. For example, if the quarterback threw 300 passes and completed 210 of them, you would divide 210 by 300 to get 0.700.

    • 2

      Subtract 0.3 from the pass completion percentage. In this example, you would subtract 0.3 from 0.7 to get 0.4.

    • 3

      Divide the Step 2 result by 0.2 to get 2. If this value exceeds 2.375, decrease it to 2.375. If it is below 0, use 0.

    • 4

      Divide the number of yards that the quarterback threw for by the number of times the quarterback threw the ball. Continuing the example, if the quarterback threw for 1,500 yards over 300 attempts, you would divide 1,500 by 300 to get five yards per attempt.

    • 5

      Subtract 3 from the yards per attempt average, then divide the result by 4. In this example, you would subtract 3 from 5 to get 2 and then divide 2 by 4 to get 0.5. If this number exceeds 2.375, reduce it to 2.375. If it is below 0, use 0.

    • 6

      Divide the number of touchdowns thrown by the number of passes attempted. In this example, if the quarterback threw for 21 touchdowns, you would divide 21 by 300 to get 0.07.

    • 7

      Divide the touchdowns per pass attempt by 0.05. Continuing the example, you would divide 0.07 by 0.05 to get 1.4. If this number exceeds 2.375, reduce it to 2.375. If it is below 0, use 0.

    • 8

      Divide the number of interceptions thrown by the number of passes attempted. In this example, if the quarterback threw 12 interceptions, you would divide 12 by 300 to get 0.04.

    • 9

      Subtract the interception rate from 0.095 and divide the result by 0.04. In this example, you would subtract 0.04 from 0.095 to get 0.055, then divide 0.055 by 0.04 to get 1.375. If this number exceeds 2.375, reduce it to 2.375. If it is below 0, use 0.

    • 10

      Add the results from steps 3, 5, 7 and 9. In this example, you would add 2 plus 0.5 plus 1.4 plus 1.375 to get a total of 5.275.

    • 11

      Multiply the result from Step 10 by 100 and divide the answer by 6 to find the passer rating. Concluding the example, you would multiply 5.275 by 100 to get 527.5 and then divide 527.5 by 6 to get a passer rating of 87.9.