Framing is the skill of receiving a borderline pitch in a way that earns a strike call. It went unmeasured for a century, got dismissed as unquantifiable, and then pitch tracking arrived and revealed it as one of the most valuable defensive skills in baseball.
Only the borderline pitches count
The core insight behind every serious framing metric: most pitches are not framed at all.
A fastball down the middle is a strike no matter who catches it. A curveball that bounces is a ball if the catcher is a statue or a Gold Glover. Neither pitch tells you anything about receiving skill. The pitches that matter are the ones near the edge of the zone, where the call genuinely could go either way — that region is called the shadow zone.
The shadow zone is the band of locations straddling the edge of the strike zone — a few inches inside and outside the boundary. Framing is decided entirely inside it.
Judging a catcher on his overall called-strike rate is misleading, because that number is driven mostly by where his pitchers threw. Isolating the shadow zone controls for that: it asks only about pitches whose outcome the catcher could plausibly have influenced.
From strike rate to framing runs
Once you have isolated shadow-zone pitches, measurement is straightforward:
- Count called strikes and total called pitches in the shadow zone.
- Compare that rate to a baseline — what a typical catcher earns on similar pitches.
- The difference, multiplied by the number of shadow-zone pitches, gives extra strikes gained or lost.
- Convert extra strikes into runs using an estimate of what one strike is worth.
That final number is framing runs. A catcher at plus five framing runs saved his team roughly five runs through receiving alone. The run conversion is an estimate, so treat framing runs as a well-grounded approximation rather than a precise count — but the ordering it produces is meaningful, and it is on the same scale as every other run-value stat, which is what makes it useful.
Where framing is won and lost
Overall framing numbers hide the coaching detail. Breaking results down by zone edge is where development actually happens, because each edge is a distinct skill:
- Bottom edge — the biggest differentiator. Receiving a low pitch with the glove working up, rather than stabbing down at it, is the technique that separates good receivers.
- Top edge — typically the hardest to steal, since umpires rarely reward a high pitch.
- Side edges — about quiet lateral receiving and beating the pitch to the spot.
Two catchers can post an identical overall shadow-zone rate while being completely different players — one earning it at the bottom of the zone, the other on the corners. Only the breakdown reveals that.
Splitting framing by pitch type is equally revealing. A catcher who steals strikes on fastballs but leaks them on breaking balls has a specific, coachable problem: receiving pitches with late downward movement. That is a practice plan, not a verdict.
Reading the numbers fairly
Two cautions. First, sample size — a single game may contain only a handful of shadow-zone pitches, which is nowhere near enough to judge anyone. Framing numbers need weeks of games before they stabilize; treat one game as a data point, not a conclusion.
Second, the catcher is not alone in the outcome. A pitcher who misses his spots badly forces his catcher to move, and a catcher who has to reach is not going to receive well. Umpire tendencies vary too. Framing metrics are a strong signal, not a sealed verdict on the person squatting behind the plate.
PitchFilthy builds a catcher framing report from any game file — shadow-zone map, framing runs, edge-by-edge breakdown, and framing split by pitch type.
See the framing report →