A quarterback rating measures the performance of a professional football quarterback based on his statistics over the course of a game, season, or career. The statistics are entered into an equation with the passer rating ranging from 0 to 158.3. Calculating the QB passer rating requires five statistics: pass attempts, pass completions, passing yards, touchdowns thrown and interceptions thrown.
QB Rating in simple steps
The QB Rating equation can be confusing when first viewed, but writing it down in advance will make things easier. The full QB Rating equation is:
QB Rating = ((Completion Equation + Yards Per Attempt Equation + Touchdowns Per Attempt Equation + Interceptions Per Attempt Equation) / 6) x 100
Calculate each part of the QB Rating equation separately.
Write down all the quarterback statistics. It can be statistics from one game, or a combination of games.
Calculate the Completion Equation. Divide the number of passes completed by the number of passes attempted. Take that answer and multiply by 100. Subtract 30 from that new answer. Divide that by 20. For example, if a quarterback completed 20 of 30 passes, the Completion Equation would be:
(((20/30) x 100) - 30) / 20 = 1.83
Calculate the Yards Per Attempt Equation. Divide the total passing yards by the number of passing attempts. Subtract 3 from that answer. Multiply that new answer by 0.25. For example, if a quarterback passed for 250 yards while attempting 30 passes, the Yards Per Attempt Equation would be:
((250/30) - 3) x 0.25 = 1.33
Calculate the Touchdowns Per Attempt Equation. Take the number of touchdown passes and divide by the number of attempts. Multiply by 100 to get the percent. Multiply that by 0.2. For example, if the quarterback threw 3 touchdown passes while attempting 30 passes, the Touchdown Per Attempt Equation would be:
((3/30) x 100) x .2 = 2
Calculate the Interceptions Per Attempt Equation. Divide the total number of interceptions by the number of pass attempts. Multiply by 100 to get the percent. Multiply by 0.25. Subtract the answer from 2.375. For example, if the quarterback threw one interception while attempting 30 passes, the Interceptions Per Attempt Equation would be:
2.375 - (((1 / 30) x 100) x 0.25) = 1.54
Calculate the final QB Rating. Add together the final answers from the Completion Equation, Yards per Attempt Equation, Touchdown per Attempt Equation and Interceptions per Attempt Equation. Divide that sum by 6. Multiply by 100. The answer will be the final QB Rating. Using the examples, the QB Rating for the quarterback would be:
QB Rating = ((1.83 + 1.33 + 2 + 1.54) / 6) x 100 = 111.7