Quarterback Rating Calculator

Calculate Quarterback Rating

Enter the quarterback’s stats below to understand how is quarterback rating calculated.

What is Quarterback Rating?

The quarterback rating (or passer rating) is a measure used in American football to assess the performance of quarterbacks or other passers. It was developed to provide a statistical measure of a quarterback’s efficiency and effectiveness based on their passing game. Knowing how is quarterback rating calculated helps in comparing player performances across different games and seasons.

The most commonly used formula is the NFL’s passer rating system, adopted in 1973. It considers four key statistics: completion percentage, yards per attempt, touchdown percentage, and interception percentage. The formula is designed so that an “average” performance results in a rating around 66.7, and a statistically “perfect” game results in a rating of 158.3.

While college football uses a different formula, the NFL rating is the standard for professional football. It’s used by fans, analysts, and teams to evaluate quarterback play, although it’s not without its critics, as it doesn’t account for factors like running ability, leadership, or the context of the game situation (e.g., performance in clutch moments).

Common misconceptions include believing a rating of 100 is “perfect” (it’s very good, but 158.3 is perfect) or that it directly translates to wins (it’s a measure of passing efficiency, not overall team success).

Quarterback Rating Formula and Mathematical Explanation

Understanding how is quarterback rating calculated involves looking at four separate components, each derived from raw passing statistics. Each component is designed to reward positive outcomes and penalize negative ones, and each is capped to prevent extreme outliers from skewing the final rating too heavily.

The four components are:

1. Completion Percentage Component (A): Based on completions per attempt.
   • Formula: `A = ((COMP / ATT) * 100 – 30) / 20`
2. Yards Per Attempt Component (B): Based on yards gained per attempt.
   • Formula: `B = ((YDS / ATT) – 3) / 4`
3. Touchdown Percentage Component (C): Based on touchdowns per attempt.
   • Formula: `C = (TD / ATT) * 20`
4. Interception Percentage Component (D): Based on interceptions per attempt.
   • Formula: `D = 2.375 – ((INT / ATT) * 25)`

Each of these components (A, B, C, and D) is capped: they cannot be less than 0 or greater than 2.375. This means even exceptionally high or low percentages in one area won’t infinitely increase or decrease the final rating beyond these bounds for each component.

The final NFL Passer Rating is then calculated as:

Passer Rating = ((A + B + C + D) / 6) * 100

Where A, B, C, and D are the capped values from the steps above.

Variables Table

Variables used in the quarterback rating formula.

Variable	Meaning	Unit	Typical Range (for calculation)
ATT	Passing Attempts	Count	1 or more
COMP	Completions	Count	0 to ATT
YDS	Passing Yards	Yards	Can be negative, usually 0 or positive
TD	Touchdown Passes	Count	0 or more
INT	Interceptions	Count	0 to ATT
A, B, C, D	Intermediate Components	Value	0 to 2.375 (each)

Practical Examples (Real-World Use Cases)

Let’s look at how is quarterback rating calculated with some examples:

Example 1: A Very Good Game

Suppose a quarterback has the following stats in a game:

• Attempts (ATT): 30
• Completions (COMP): 25
• Yards (YDS): 300
• Touchdowns (TD): 3
• Interceptions (INT): 0

Calculating the components:

• A = ((25 / 30) * 100 – 30) / 20 = (83.333 – 30) / 20 = 53.333 / 20 = 2.666, capped at 2.375
• B = ((300 / 30) – 3) / 4 = (10 – 3) / 4 = 7 / 4 = 1.75
• C = (3 / 30) * 20 = 0.1 * 20 = 2.0
• D = 2.375 – ((0 / 30) * 25) = 2.375 – 0 = 2.375

Rating = ((2.375 + 1.75 + 2.0 + 2.375) / 6) * 100 = (8.5 / 6) * 100 = 1.4166 * 100 = 141.7 (rounded)

This is an excellent passer rating, reflecting a highly efficient performance with a high completion rate, good yards per attempt, a solid TD rate, and no interceptions.

Example 2: A Below Average Game

Suppose a quarterback has these stats:

• Attempts (ATT): 35
• Completions (COMP): 18
• Yards (YDS): 190
• Touchdowns (TD): 1
• Interceptions (INT): 2

Calculating the components:

• A = ((18 / 35) * 100 – 30) / 20 = (51.428 – 30) / 20 = 21.428 / 20 = 1.071
• B = ((190 / 35) – 3) / 4 = (5.428 – 3) / 4 = 2.428 / 4 = 0.607
• C = (1 / 35) * 20 = 0.02857 * 20 = 0.571
• D = 2.375 – ((2 / 35) * 25) = 2.375 – (0.05714 * 25) = 2.375 – 1.428 = 0.947

Rating = ((1.071 + 0.607 + 0.571 + 0.947) / 6) * 100 = (3.196 / 6) * 100 = 0.5326 * 100 = 53.3 (rounded)

This rating is below average, indicating struggles with completion percentage, lower yards per attempt, and a higher interception rate relative to touchdowns.

How to Use This Quarterback Rating Calculator

Using our calculator is straightforward:

1. Enter Attempts: Input the total number of passing attempts the quarterback made. This must be greater than zero.
2. Enter Completions: Input the number of passes that were successfully completed. This cannot be more than the attempts.
3. Enter Yards: Input the total passing yards gained (or lost).
4. Enter Touchdowns: Input the number of touchdown passes thrown.
5. Enter Interceptions: Input the number of interceptions thrown.

As you enter the values, the calculator will automatically update the Passer Rating and the four intermediate components (A, B, C, and D) in real-time. The bar chart will also update to visually represent the contribution of each component.

Reading the Results: The primary result is the NFL Passer Rating. A rating of 158.3 is perfect, around 90-100+ is generally considered very good to elite, 75-90 is good to average, and below 60-70 is below average or poor. The intermediate results show how each aspect of passing contributed to the overall rating. Understanding how is quarterback rating calculated helps interpret these components.

Decision-Making: While not a direct predictor of wins, the passer rating is a useful tool for evaluating a quarterback’s passing efficiency. Coaches and analysts use it to identify areas of strength and weakness. A low ‘A’ component might indicate accuracy issues, while a low ‘B’ could mean the QB isn’t pushing the ball downfield effectively or receivers aren’t gaining yards after the catch.

Key Factors That Affect Quarterback Rating Results

Several factors directly influence how is quarterback rating calculated:

1. Completion Percentage (A): Higher completion rates directly boost component A and thus the overall rating. Accuracy, receiver skill, and play-calling impact this.
2. Yards Per Attempt (B): The ability to gain more yards per pass attempt, either through deep throws or yards after catch, increases component B. O-line protection and receiver ability play a role.
3. Touchdown Rate (C): Throwing touchdowns at a higher rate per attempt significantly increases component C. Red-zone efficiency is key here.
4. Interception Rate (D): Minimizing interceptions is crucial. A lower interception rate per attempt leads to a higher component D. Decision-making and ball security are vital.
5. Number of Attempts (ATT): While not directly in the final formula after components are calculated, a very low number of attempts can make the percentages volatile. The rating becomes more stable with more attempts.
6. Game Context (Not in formula): The formula doesn’t account for the situation (e.g., a 2-yard completion on 3rd and 1 is more valuable than on 1st and 10), opponent strength, or weather, but these factors influence the raw stats that go into the rating.

Frequently Asked Questions (FAQ)

1. What is a perfect passer rating?

A perfect passer rating in the NFL system is 158.3. This is achieved when a quarterback meets or exceeds a 77.5% completion rate, 12.5 yards per attempt, an 11.875% touchdown rate, and a 0% interception rate, leading to each component being capped at 2.375.

2. Is a passer rating of 100 good?

Yes, a passer rating of 100 or above is generally considered very good to excellent for a game or a season.

3. Can a quarterback have a negative passer rating?

No, the lowest possible value for each component (A, B, C, D) is 0, so the lowest possible passer rating is 0.0.

4. Does the quarterback rating formula account for rushing yards or touchdowns?

No, the standard NFL passer rating only considers passing statistics. A quarterback’s rushing contributions are not factored in. This is one reason why other metrics like QBR (Total Quarterback Rating) were developed.

5. Why is there a cap on each component?

The caps (0 to 2.375) prevent extreme performances in one area (like an incredibly high completion percentage on very few attempts) from disproportionately inflating or deflating the overall rating. It balances the contributions of the four aspects.

6. How is college football passer rating different?

College football uses a different formula that results in a different scale, often with higher numbers. It is calculated as: `(8.4 * YDS) + (330 * TD) + (100 * COMP) – (200 * INT) / ATT`. It doesn’t use the capped component system of the NFL.

7. What if a quarterback has zero attempts?

The formula involves division by attempts (ATT). If attempts are zero, the rating is undefined or typically considered 0 by convention if no passes were thrown. Our calculator requires at least 1 attempt for a valid calculation.

8. Is quarterback rating the best way to evaluate a QB?

It’s a useful metric for passing efficiency but not the sole determinant of a QB’s value. Leadership, running ability, decision-making under pressure, and context of performance are also important and not fully captured by the rating.