Baseball Savant has become the nerve center for the sport’s most detailed statistical analysis, turning raw video into a library of measurable events that were once left to intuition.
Redefining the Game
At the heart of that library is the concept of a 'hard‑hit ball', defined by Statcast as any batted ball that leaves the bat at 95 mph or faster, a threshold that correlates strongly with offensive production.
From there, newer metrics such as xBA and xwOBA expand the picture. xBA estimates the probability that a given batted ball will become a hit by factoring exit velocity and launch angle, while xwOBA adds sprint speed into the equation, offering a more nuanced view of on‑base ability.
EV50, another cornerstone, captures the average exit velocity of a batter’s hardest half of balls in play, and its counterpart for pitchers measures the softest half of balls they allow, highlighting differences in contact quality.
Adjustments like Adjusted EV, which caps the maximum recorded velocity at 88 mph, and precise bat‑speed measurements at the sweet spot — where swings of 75 mph or more are considered fast — provide deeper insight into swing mechanics.
Swing path characteristics, including tilt and arc angles, are tracked in three‑dimensional space, while ideal attack angles for a ball sit between five and twenty degrees, a range that maximizes launch efficiency.
Pitchers benefit from similarly granular data: pitch movement is expressed in inches relative to league averages, and active spin quantifies the portion of spin that actually contributes to that movement. The resulting xERA translates xwOBA into an ERA‑like figure, giving a more intuitive sense of pitching effectiveness.
Defensive metrics are equally detailed. Catcher reaction time, measured from glove to base transition, and fielder throw speed in miles per hour help evaluate arm strength, while range‑based skill metrics quantify outs saved compared with peers. Outfielders’ catch probability is reported as a percentage, and runners’ ranging distances are logged at the moment of pitch release.
Speed remains a separate axis of analysis. Top running speed, recorded in feet per second during a player’s fastest one‑second burst, defines a 'Bolt' when it reaches 30 ft/s or more, a benchmark that underscores the importance of baserunning in modern strategy.