Passer rating (American and Canadian football)

What the rating represents

At its core, passer rating combines several passing outcomes into a single index so observers can compare performers across games or seasons. Typical inputs are completion rate, yards gained per attempt, percentage of passes that result in a touchdown, and percentage that end in an interception. The resulting number is intended to rise as completions, yardage and scoring increase and to fall as turnovers increase.

Components and common formulas

• Completion percentage — proportion of passes caught by a receiver.
• Yards per attempt — average distance gained on each pass attempt.
• Touchdown percentage — touchdowns thrown relative to attempts.
• Interception percentage — interceptions relative to attempts.

The National Football League (NFL) uses a specific formula that blends these four components and applies scaling limits; its highest possible result is commonly cited as 158.3, often called a "perfect" rating. College football (NCAA) employs a different arithmetic expression, frequently labeled "pass efficiency," which produces numbers on a different scale. American football and Canadian football sources may report similar but non-identical metrics depending on local conventions.

History and variations

Passer rating concepts arose in the 20th century as statisticians sought concise summaries of passing performance. Over time the NFL and collegiate bodies adopted distinct formulas to reflect their priorities and sample sizes. Professional and amateur record-keeping practices, as well as competing advanced metrics, have continued to evolve, so comparisons across eras and leagues require care.

Uses, examples and limitations

Coaches, analysts and fans use passer rating to compare quarterbacks, evaluate performances in single games, and summarize season-long production. It is simple to compute and broadly understood, but it has recognized limits: it treats each play in isolation, does not account for dropped passes, pass rush or sacks, and can be influenced by small sample sizes. Because leagues use different formulas, a passer rating from one league is not directly equivalent to the same numeric rating in another.

As a result, passer rating remains a useful but imperfect tool. For richer context, analysts often combine it with situational stats and more advanced measures that adjust for game context, opponent quality and play difficulty.