IHM Knowledge Center
What Is Corsi in Hockey?
How do analysts use shot attempts to estimate puck possession and overall game control?
Editor: Coach Mark • Updated: April 26, 2026
Short Answer
Corsi is a statistic that counts all shot attempts, including shots on goal, missed shots, and blocked shots. It is used as a proxy for puck possession and offensive pressure.
Full Explanation
Corsi is one of the foundational metrics in hockey analytics. It tracks every attempt to direct the puck toward the net.
This includes:
- Shots on goal
- Missed shots
- Blocked shots
The idea behind Corsi is simple. Teams that control the puck more tend to generate more shot attempts over time.
Because direct possession time is difficult to track accurately, Corsi is used as a practical way to estimate which team is controlling play.
Corsi is often expressed as a percentage. If a team has 55 percent Corsi, it means they are taking more shot attempts than their opponent.
How Corsi Reflects Game Control
Corsi helps show which team is spending more time in the offensive zone and applying pressure.
Teams with strong Corsi numbers typically:
- Control puck possession
- Maintain offensive zone time
- Force opponents to defend
However, Corsi does not measure shot quality. A team can have strong Corsi but still create low-danger chances.
This is why Corsi should be combined with other metrics like expected goals and high-danger chances.
NHL vs IIHF Context
Corsi is most commonly used in NHL analytics due to detailed tracking data.
In IIHF hockey, the same concept applies, but interpretation may vary depending on style of play and data availability.
The core principle remains the same across all levels.
Why Corsi Is Controversial
Corsi is controversial because it does not differentiate between dangerous and non-dangerous shots.
Fans may see a high Corsi percentage and assume dominance, but coaches understand that not all shot attempts create real scoring threats.
A team may generate many low-quality shots while the opponent focuses on fewer but better chances.
This difference creates debate about how much value Corsi should have in evaluation.
Edge Case: High Corsi but Weak Offense
A key edge case occurs when a team has strong Corsi numbers but struggles to score.
This usually happens when:
- Most shots come from the perimeter
- The slot is well defended
- The goalie has clear visibility
- There is little pre-shot movement
In this case, Corsi reflects pressure but not effective offense.
This is why combining Corsi with shot quality metrics is critical.
IHM Signal System: How to Read Corsi
To interpret Corsi correctly, focus on these signals:
- Shot location: Are attempts coming from dangerous areas?
- Game state: Is the team leading or trailing?
- Shot type: Quick chances or low-danger volume?
- Defensive structure: Is the opponent allowing outside shots?
- Trend: Is Corsi consistent over time?
Trigger-level rule:
If a team has high Corsi but low high-danger chances, the offensive pressure is almost always inefficient.
This is one of the most important signals when using Corsi.
IHM Insight: Why Corsi Is Misunderstood
Corsi is often misunderstood because it is treated as a direct measure of dominance.
In reality, it measures volume, not quality.
Two teams can have similar Corsi numbers but very different scoring potential depending on how those shots are created.
Understanding this difference is essential for proper analysis.
Mini Q&A
What does Corsi measure?
Total shot attempts.
Is Corsi the same as possession?
No, but it is used as a proxy.
What is a good Corsi percentage?
Above 50 percent.
Does Corsi measure scoring chances?
No, only shot attempts.
Should Corsi be used alone?
No, it should be combined with other metrics.
Why This Rule Exists
Corsi exists to provide a simple way to measure puck possession and offensive pressure through shot attempts.
It allows analysts to compare teams and players even when direct possession data is not available.
Key Takeaways
- Corsi counts all shot attempts
- It is used as a proxy for possession
- High Corsi means more offensive pressure
- It does not measure shot quality
- Context is required for proper interpretation