The Lombardi Calculator computes the official National Football League passer rating from five raw box-score numbers: pass attempts, completions, passing yards, touchdowns, and interceptions. The result is the familiar 0.00-to-158.33 score you see next to a quarterback's name every Sunday — the same metric the NFL has used since 1973, often called the "Lombardi" rating after the trophy.
Type in a line from any game, any season, or any prospect's college tape, and the score updates instantly. Below the number you get the four hidden components the formula combines, so you can see exactly why a quarterback with the same completion rate can rate very differently depending on yards per attempt and interceptions.
How to Use
- Enter Pass Attempts — the total number of times the quarterback dropped back to throw. This is the denominator for every component, so it must be greater than zero.
- Enter Completions — the number of catchable passes that were hauled in. If you type a completion count higher than attempts, the calculator flags an error.
- Enter Passing Yards — net passing yards for the game or season, including any yardage lost on sacks that the box score already nets out.
- Enter Touchdowns — passing touchdowns only; rushing touchdowns and receiving touchdowns do not count.
- Enter Interceptions — every pass picked off, including deflected picks and Hail Mary heaves that get intercepted at the end of a half.
The result card shows the final Passer Rating on a 0–158.3 scale, plus the underlying Completion %, Yards per Attempt, TD %, and INT %. Four component rows (A, B, C, D) reveal how close each piece is to the 2.375 ceiling, which is the easiest way to spot what a quarterback needs to clean up.
The Formula, Step by Step
The NFL passer rating was designed by Don Smith for the Pro Football Hall of Fame in 1973 to replace a messy collection of ad-hoc metrics. It converts five raw stats into four partial scores, caps each one, and averages them:
- Component A = ((Completions ÷ Attempts) − 0.30) × 5
- Component B = ((Yards ÷ Attempts) − 3.0) × 0.25
- Component C = (Touchdowns ÷ Attempts) × 20
- Component D = 2.375 − ((Interceptions ÷ Attempts) × 25)
Each component is then clamped between 0.000 and 2.375. That clamp is what makes the scale bounded: no matter how great a game is, the highest possible single score is 158.33 (a "perfect" rating), and no matter how ugly, the floor is 0.00.
Final Passer Rating = ((A + B + C + D) ÷ 6) × 100.
The divisor of 6 (rather than 4) and the multiplier of 100 are deliberate scale choices. They mean an "average" NFL line — roughly a 60% completion rate, 7 yards per attempt, a 5% TD rate, and a 3% INT rate — lands near 80, which is why 90+ seasons are considered good and 100+ is Pro Bowl territory.
Examples
Example 1 — A respectable regular-season line. 30 completions on 50 attempts, 300 passing yards, 2 touchdowns, 1 interception. Completion % is 60%, yards per attempt is 6.0, TD % is 4.0%, INT % is 2.0%. Plugging in: A = (0.60 − 0.30) × 5 = 1.50, B = (6.0 − 3.0) × 0.25 = 0.75, C = (0.04) × 20 = 0.80, D = 2.375 − (0.02 × 25) = 1.875. Sum = 4.925, divided by 6 × 100 = 82.08. That is a solid, game-manager performance — good enough to win if the defense shows up, but not the kind of line that wins MVP awards.
Example 2 — A historic MVP season. 343 completions on 502 attempts, 4,643 yards, 45 touchdowns, 6 interceptions. Completion % is 68.3%, yards per attempt is 9.25, TD % is 9.0%, INT % is 1.2%. Every component hits the ceiling on one axis or another. The final rating comes out to 122.46 — the kind of number that wins MVPs and leads the league by a wide margin.
Example 3 — A perfect game. 10 completions on 10 attempts, 200 yards, 2 touchdowns, 0 interceptions. Completion % is 100%, yards per attempt is 20.0, TD % is 20%, INT % is 0%. Every component clamps to 2.375, and the final rating is 158.33. That is the theoretical ceiling — the reason announcers call a 158.3 line "perfect."
What the Number Does and Does Not Tell You
Passer rating measures passing efficiency only. It rewards accuracy, yards per attempt, touchdown frequency, and ball security. It ignores sacks, rushing production, crunch-time comeback wins, dropped passes, deflected balls, weather, field position, and the quality of the opposing defense. A quarterback playing from behind for three quarters can post a gaudy rating while his team loses; a quarterback protecting a 17-point lead can post a quiet 75 rating while his team wins easily.
Use the Lombardi Calculator as a quick, apples-to-apples summary of a passing line, not as a verdict on who is the better player. Pair it with wins over expectation (EPA/WPA), clutch stats, and film study for the full picture.
Examples in Context
- A 158.3 game means every component hit the ceiling; roughly a dozen such performances happen across the NFL in a typical season.
- A 100+ season is Pro Bowl-caliber. The league leader usually sits between 105 and 115.
- A 90–100 line means above-average starter play.
- An 80–90 line means a regular starter who can win if surrounded by talent.
- Below 70 usually means a rookie learning on the job, an injured veteran, or a backup thrust into action.
FAQ
How is the Lombardi passer rating calculated?
The NFL passer rating combines four components — completion percentage, yards per attempt, touchdown percentage, and interception percentage — into a single 0–158.3 score. Each component is clamped between 0 and 2.375, then summed, divided by 6, and multiplied by 100. This calculator performs that formula in real time from the five box-score inputs.
What is a perfect passer rating?
A perfect rating is 158.33. It happens when every component hits the 2.375 ceiling: 77.5%+ completion rate, 12.5+ yards per attempt, 11.875%+ touchdown rate, and 0 interceptions. Very few quarterbacks have thrown a perfect game in the regular season, and none have done it more than twice in a career.
Why is the maximum 158.3 and not 100?
The formula was calibrated in 1973 so that an average NFL line lands near 80, Pro Bowl play near 100, and a historically great line near 115–125. The 158.3 ceiling comes from the 2.375 cap on each of four components: (2.375 × 4) ÷ 6 × 100 = 158.33. The odd number is a deliberate scale choice, not a rounding error.
Why does the formula divide by 6 instead of 4?
Dividing by 4 and multiplying by 100 would give a maximum of 237.5. The designers chose to divide by 6 so the 100-point mark lines up with "excellent" play rather than "average" play. The effect is that an 80 rating reads as league-average, which matches how football fans and announcers already talk about the stat.
Does passer rating include sacks or rushing yards?
No. The official NFL passer rating uses only completions, attempts, passing yards (net of sack yardage already counted in the official box score), passing touchdowns, and interceptions. Sack yards and rushing production are tracked separately by the NFL and are not part of this formula.
What is a good passer rating for a quarterback?
For a full NFL season, a rating above 100 is Pro Bowl-caliber, 90–100 is a strong starting line, 80–90 is league average, and below 75 typically means the quarterback is under pressure to improve or be replaced. Single-game ratings swing much wider because of small sample size — a single 158.3 game does not a Hall of Famer make.
How is the Lombardi rating different from ESPN QBR?
ESPN's Total QBR is a separate, proprietary formula that factors in sacks, rushing, game situation, and dropped passes on a 0–100 scale. The NFL passer rating (this calculator) is a transparent, public formula that uses only the five passing box-score stats on a 0–158.3 scale. They often disagree, especially on running quarterbacks.
Disclaimer
This Lombardi Calculator is provided for informational purposes only and does not constitute scouting, coaching, fantasy, or gambling advice. Outputs are computed from the official NFL passer rating formula using the numbers you enter; real box-score lines may differ slightly due to stat-keeper rulings, sack handling, and post-game corrections. Always cross-check against the official NFL gamebook and your league's scoring rules before making roster, lineup, or betting decisions.